M119 94 E420 no start (Carbon on valves)

[samm]

Re: m119 94 E420 no start

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[samm]

Re: m119 94 E420 no start

I will be checking more things on the car in a couple days. At work everyday. .. :-(

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[samm]

Re: m119 94 E420 no start

https://www.youtube.com/watch?app=desktop&persist_app=1&v=v9IRusTgrus

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[video=youtube;v9IRusTgrus]https://www.youtube.com/watch?&v=v9IRusTgrus[/video]

 

[samm]

Re: m119 94 E420 no start

Guys please watch this v short video to hear the weird cranking.
Gsxr in particular and any other experienced people please listen to it.
I hope you can help me.
I would actually buy whoever helps me figure this out a nice lunch. I know you are probably far away from SoCal but I can paypal it to you!

Thank you

Sam

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[Ascension]

Re: m119 94 E420 no start

Sounds to me like it's just spinning with no compression wonder if the timing chain snapped?? Easy way to tell would be have someone turn it over with one of the the caps off ( with the ignition disabled!!) to see if the rotor is turning.

 

[samm]

Re: m119 94 E420 no start

Sounds to me like it's just spinning with no compression wonder if the timing chain snapped?? Easy way to tell would be have someone turn it over with one of the the caps off ( with the ignition disabled!!) to see if the rotor is turning.

Hi and thank you for your input...
Wow. What a disaster that will be of the chain snapped!
It certainly will be a massive shock and a warning to other m119 owners. Car has 125k on it.
Not some crazy miles.
I guess my diagnosis will continue on Christmas eve. :-(

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[Ascension]

Re: m119 94 E420 no start

I hope I am hearing that wrong through the speakers here but it sounds like that motor is spinning with no compression. Let us know what the verdict is as I own a 95 E420 with similar miles.

 

[Klink]

Re: m119 94 E420 no start

Don't panic yet. That does not sound at all like a M119 engine without compression.

 

[samm]

Re: m119 94 E420 no start

Don't panic yet. That does not sound at all like a M119 engine without compression.

Well I hope you are right!!
I still think the most important clue is that it was cold in the morning. The car
Started and ran very roughly fir about 30 seconds. I pressed the accelerator and it stalled. Then never switched on again.

Someone suggested blocked catalytic converters. But wouldn't I have got some kind of warning? I didn't see any loss of power or anything leading to this incident....

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[samiam44]

Re: m119 94 E420 no start

Is the cps working?



Michael

 

[gsxr]

Re: m119 94 E420 no start

The cranking does sound abnormal but you'd need to get an audio/video clip of the engine compartment (not from inside the car).

Doubtful the chain snapped, sure hope not as this is an interference engine. Have someone else crank it over while you look through the oil fill hole and watch the cams move.

If the cats are REALLY plugged bad, that can prevent the engine from starting, but that is not likely. You could loosen the front exhaust crossover pipe joint (or, pull the 02 sensor) as a test but neither of those are fun jobs on the street.

Back to basics - have you pulled all 8 plugs for a visual inspection? Wet? Dry? Fouled? All 8 look the same or not? Etc...

Warning: A used starter may not be any better than your old one. As long as your engine is cranking, a different starter probably will not make any difference.

 

[samm]

Re: m119 94 E420 no start

Is the cps working?



Michael

Hi yes I replaced the crankshaft position sensor with a known working item.
Unfortunately made zero difference...

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[lowman]

Re: m119 94 E420 no start

i think it sounds like there is low compression...and..it also seems like its turning slow...

 

[samm]

Re: m119 94 E420 no start

The cranking does sound abnormal but you'd need to get an audio/video clip of the engine compartment (not from inside the car).

Doubtful the chain snapped, sure hope not as this is an interference engine. Have someone else crank it over while you look through the oil fill hole and watch the cams move.

If the cats are REALLY plugged bad, that can prevent the engine from starting, but that is not likely. You could loosen the front exhaust crossover pipe joint (or, pull the 02 sensor) as a test but neither of those are fun jobs on the street.

Back to basics - have you pulled all 8 plugs for a visual inspection? Wet? Dry? Fouled? All 8 look the same or not? Etc...

Warning: A used starter may not be any better than your old one. As long as your engine is cranking, a different starter probably will not make any difference.

Well that may offer some reprieve for my tortured mind.
I hope there is no major engine trouble. I am in a very difficult time right now. My life is in transition and I have extremely limited money.
U just don't expect major things to wrong with a car with 125k.
But the Trans already went and has been replaced. What's next. :-(


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[Raffaelli]

Re: m119 94 E420 no start

Sounds like low compression to me :/

 

[gsxr]

Re: m119 94 E420 no start

Something to keep in mind... low compression (or no compression) would result in the engine spinning faster than normal. Samm is saying his engine is cranking slower than normal.

 

[samm]

Re: m119 94 E420 no start

Something to keep in mind... low compression (or no compression) would result in the engine spinning faster than normal. Samm is saying his engine is cranking slower than normal.

Yes sir
The car is cranking slower than normal. I mean many of you have m119 engines so I would welcome your inputs....
Well tomorrow I will be doing more diagnostic work and will have more info. I want to keep everyone updated in case someone runs into this problem in the future.


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[lowman]

Re: m119 94 E420 no start

Something to keep in mind... low compression (or no compression) would result in the engine spinning faster than normal. Samm is saying his engine is cranking slower than normal.

I agree it will maybe cranking "faster"...with no compression...but the SOUND can fool you to think its going SLOWER..as you will have LESS cylinders that actually "fires" ...which again makes the frequensy of the "cranking " sound SLOWER..thats what im getting at least...abit hard to explain.

And when i went back and listened to it now..i can reaaally feel that it sounds like there is LOW ..or LITTLE compression...aaand a weak battery.

 

[lowman]

Re: m119 94 E420 no start

Yes sir
The car is cranking slower than normal. I mean many of you have m119 engines so I would welcome your inputs....
Well tomorrow I will be doing more diagnostic work and will have more info. I want to keep everyone updated in case someone runs into this problem in the future.


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You should do a compression test first of all. thats the route i would go...if the compression is not where its supposed to be...then you will never get it to start or run.
Check out this video...obviously it is a 4 cylinder..but you can kinda hear the same " non jumpy compreesiony engine..just like there is no ..or LESS resistance in the engine..
Skip to 1min 40 seconds "ish..

[video=youtube;9KcA6n3o4tI]https://www.youtube.com/watch?v=9KcA6n3o4tI[/video]

 

[samm]

Re: m119 94 E420 no start

You should do a compression test first of all. thats the route i would go...if the compression is not where its supposed to be...then you will never get it to start or run.
Check out this video...obviously it is a 4 cylinder..but you can kinda hear the same " non jumpy compreesiony engine..just like there is no ..or LESS resistance in the engine..
Skip to 1min 40 seconds "ish..

[video=youtube;9KcA6n3o4tI]https://www.youtube.com/watch?v=9KcA6n3o4tI[/video]

Thank you for the useful video...
I will be doing a compression test today. First time I ever do this, so it will be interesting.
I will write down the psi values per cylinder....
[emoji106]

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[lowman]

Re: m119 94 E420 no start

good stuff.just take it easy..and do this first and take it from there.
You also want to look for big differences in the compression...not sooooo important what the "pressure" is...but more important that the cylinders are more or less the same in compression.The actual spec of how much compression it should have..i really dont know exact.
The engine should be warm when doing this..and remember to remove all spark plugs when doing the test..and also you should disconnect the coil,and the throttle should be pressed down fully to make the throttle flap stay fully open.


ALSO..this would be the time to check if ANY of the sparkplugs are even remotly loose...that could lead to low compression aswell..even though you would then again HEAR it like "spitting" the compression...like "hissing" sound on each "compression stroke"..
Again i want to point out that im not saying there IS low compression...im just saying thats what i hear when i hear the video.And my suggestion to check the compression...is to have that ruled out of the equation
i want to wish you suuuuper good luck mate

 

[samm]

Re: m119 94 E420 no start

U know guys. I bought this m119 car because all I've ever read over the years is that it's a bullet proof engine.
But...if it turns out that the timing chain skipped or snapped then I would completely disagree with the bullet proof assessment.
But anyway. When I do the compression test..if there is no compression what does this mean? That the Crankshaft and camshafts are not connected by the timing chain?

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[samm]

Re: m119 94 E420 no start

good stuff.just take it easy..and do this first and take it from there.
You also want to look for big differences in the compression...not sooooo important what the "pressure" is...but more important that the cylinders are more or less the same in compression.The actual spec of how much compression it should have..i really dont know exact.
The engine should be warm when doing this..and remember to remove all spark plugs when doing the test..and also you should disconnect the coil,and the throttle should be pressed down fully to make the throttle flap stay fully open.


ALSO..this would be the time to check if ANY of the sparkplugs are even remotly loose...that could lead to low compression aswell..even though you would then again HEAR it like "spitting" the compression...like "hissing" sound on each "compression stroke"..
Again i want to point out that im not saying there IS low compression...im just saying thats what i hear when i hear the video.And my suggestion to check the compression...is to have that ruled out of the equation
i want to wish you suuuuper good luck mate

Lowman
Thank you for your advice...one question though...I cannot get the car Started so how can I get the engine warm?

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[lowman]

Re: m119 94 E420 no start

Lowman
Thank you for your advice...one question though...I cannot get the car Started so how can I get the engine warm?

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oh yes..sorry..well...just try and do it when it got some "heat" in it..like..not standing out in 20minus degrees celcsius.


and when it comes to what to do if the car has "less" or no compression..that you will have to deal with then.And NO compression means that the Cylinder is not holding the pressure that the piston creates.so either leaking through valves...head gasket,or through piston/ or piston rings.


But it really dont think it has snapped...the chain that is..then you wouldnt be able to turn over the engine most likely.
It can possibly it has skipped because of maybe the guide rails disintegrated..or something.
But do the compression test first..i think that will tell you alot,,do you have a friend that can help you out?

 

[samm]

Re: m119 94 E420 no start

oh yes..sorry..well...just try and do it when it got some "heat" in it..like..not standing out in 20minus degrees celcsius.


and when it comes to what to do if the car has "less" or no compression..that you will have to deal with then.And NO compression means that the Cylinder is not holding the pressure that the piston creates.so either leaking through valves...head gasket,or through piston/ or piston rings.


But it really dont think it has snapped...the chain that is..then you wouldnt be able to turn over the engine most likely.
It can possibly it has skipped because of maybe the guide rails disintegrated..or something.
But do the compression test first..i think that will tell you alot,,do you have a friend that can help you out?

Well believe it or not I have nobody that can help me at all.
I do not have any family here. A couple of friends who are far away. Unfortunately.
Maybe I can ask a neighbour..

By the way the car is in San Clemente in orange county right now. So the Temps are not too cold I think...

I haven't been able to do a spark test yet because I don't have anyone to turn the key. That's why u just went ahead and changed several parts because I can do thst on my own .

I will report back though today! Thanks Lowman [emoji106] [emoji4]


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[gsxr]

Re: m119 94 E420 no start

But...if it turns out that the timing chain skipped or snapped then I would completely disagree with the bullet proof assessment.
But anyway. When I do the compression test..if there is no compression what does this mean? That the Crankshaft and camshafts are not connected by the timing chain?

Uh, hold on a sec here... before you get too crazy, do the simple test I mentioned before. Have someone crank the engine while you look through the oil fill hole. If you see the camshafts turn, the chain is NOT broken.

It's not likely the chain has jumped either - but you'd have to pull both valve covers to check this. I can't think of anyone ever reporting a jumped timing chain on an M119.

Also: Performing a compression test on the M119 is not a piece of cake. The factory manual says to only use a remote starter switch to crank with the key OFF. I don't think you will have the tools available to do this, so if you crank with the key you MUST disconnect the EZL first, and also pull the fuel pump relay. This will ensure there is no fuel or spark while cranking. And you have to pull all 8 spark plugs out before testing. And you need a good, fully charged battery. And you need a good starter or the results will be inaccurate. And it isn't easy to get the aftermarket compression tester hose threaded into the threads at the bottom of the deep hole. And if you booger up the threads, or tighten the tester too much and can't get it unscrewed, you are screwed. I've done M119 compression testing many times, I would not go there unless you rule out a lot of other things first. Just sayin'...

Klink, if you're out there, would love to hear your $0.02!

 

[lowman]

Re: m119 94 E420 no start

oohhh thats to bad.i feel for you mate.
hopefully a neighbour will help you out abit.
yeah no problem at all helping out if it is even a little help

looking forward to hear what you find.

cheers

 

[samm]

Re: m119 94 E420 no start

Guys this is the closest sound I can find on you tube that sounds similar to my car. I know I will do my own checks today...just curious because I have never seen this problem before in 15 years fixing all my cars.

[video=youtube;hNqCekY0Rp8]https://www.youtube.com/watch?v=hNqCekY0Rp8[/video]

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[samm]

Re: m119 94 E420 no start

Of course my car doesn't start at at all

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[lowman]

Re: m119 94 E420 no start

and as GSXR mentioned..also disonnect the EZL...just disconnect the wire that is the crank sensor wire.

and yes..fully charged battery,and the tester itself..its possible to use the tester with a rubber cone end that you put down in the sparkplug hole..which makes it easier and less dangerous regarding the "damaging threads" part.

Testing the compression on a m119 isnt that different than any other engine...but yes it is important to disconnect stuff that makes fuel go into the engine..but that goes for every engine.and the remote key starter..that is just so you will be able to do the whole procedure yourself withouth having to have another person using time on something that can be done by just one person

 

[lowman]

Re: m119 94 E420 no start

Guys this is the closest sound I can find on you tube that sounds similar to my car. I know I will do my own checks today...just curious because I have never seen this problem before in 15 years fixing all my cars.

https://youtu.be/hNqCekY0Rp8

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indeed...the same "sound" as in the 4 cylinder movie i posted...so..if you reckognize this sound in the video you posted...i totally stand for my suggestion about testing your engine compression ...as in your video..i really think it sounds the same as the other two videos...even though it seems also your battery is not very up to charge.


And another thing..this does not have to do with timing chain or guides...it can also be hydraulic lifter problem.

 

[samm]

Re: m119 94 E420 no start

Uh, hold on a sec here... before you get too crazy, do the simple test I mentioned before. Have someone crank the engine while you look through the oil fill hole. If you see the camshafts turn, the chain is NOT broken.

It's not likely the chain has jumped either - but you'd have to pull both valve covers to check this. I can't think of anyone ever reporting a jumped timing chain on an M119.

Also: Performing a compression test on the M119 is not a piece of cake. The factory manual says to only use a remote starter switch to crank with the key OFF. I don't think you will have the tools available to do this, so if you crank with the key you MUST disconnect the EZL first, and also pull the fuel pump relay. This will ensure there is no fuel or spark while cranking. And you have to pull all 8 spark plugs out before testing. And you need a good, fully charged battery. And you need a good starter or the results will be inaccurate. And it isn't easy to get the aftermarket compression tester hose threaded into the threads at the bottom of the deep hole. And if you booger up the threads, or tighten the tester too much and can't get it unscrewed, you are screwed. I've done M119 compression testing many times, I would not go there unless you rule out a lot of other things first. Just sayin'...

Klink, if you're out there, would love to hear your $0.02!

Good day gsxr
Well I will open the oil filler cap. I will try to put my phone near it and record a video while crank. If not then maybe I can turn the crankshaft bolt by hand and look at the camshafts to see if they turn...
I hear what you are saying about the compression test complications. That will be my last test then I guess.

I mean compression test is to see if there are leaks right? So would a leak be the cause of my issue. Bearing in mind my particular symptoms in this case?

I struggle to think a leak in the cylinder is the cause. But will see...

[emoji106] [emoji107]

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[samm]

Re: m119 94 E420 no start

indeed...the same "sound" as in the 4 cylinder movie i posted...so..if you reckognize this sound in the video you posted...i totally stand for my suggestion about testing your engine compression ...as in your video..i really think it sounds the same as the other two videos...even though it seems also your battery is not very up to charge.


And another thing..this does not have to do with timing chain or guides...it can also be hydraulic lifter problem.

Yes you are correct...it does sound similar to the other video you posted...well I will do the compression test as the final test. Gsxr has warned me about potential complications with the compression test. But if I have to do it I will, after I confirm other things first.
In a few hours I suppose I will have more to report back chaps! [emoji4]

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[lowman]

Re: m119 94 E420 no start

yes...thats good.
but as long as you make shure you dont get any fuel inside the engine..there is no more complications doing a compression test on an m119 compared to another engine.
But making shure the fuel does not get into the engine when cranking to check compression....that goes for no matter what engine.

but like i said...it can also be a hydraulic valve lifter /lifters that can cause this.

but i guess youll find out

 

[Klink]

Re: m119 94 E420 no start

Actually, it sounds a little bit like what happens when carbon falls off the valves and sticks them open just as you are cranking. Some of the valves get stuck open, and then the oil pressure enters the lifters thereby taking up the space and holding some valves open. And in extremely rare cases, a sticking oil pressure relief valve in the oil pump will push some of the valves off of the valve seats just as the engine starts. In each scenario you get crank and engine start, immediately followed by engine stall and a weird sound on attempted restarts, as yours seems to be doing. However, that restart cranking speed will usually seem a little high, not a little low, as yours seems to sound. Maybe your battery is a little weak after restart attempts.

Everyone seems to have hit most of the basics, but I want to repeat that you check your battery terminals, most especially the small additional wires that are on the positive battery terminal for good condition and contact, etc. etc.

Make sure that while your key is in the run position, and while you were cranking that the row of warning bulbs at the bottom of the instrument panel stay illuminated. Ignition switches can develop poor contact on circuits other than the cranking circuit, then the combined voltage drop from cranking demand along with voltage drop in the switch can cause the other important circuits to be low on voltage while you are cranking. A common contact to experience this anomaly is the one that feeds the ignition system. Do you have spark coming from the coils? No spark could mean a faulty ignition switch. Unfortunately, sudden EZL death has the same symptoms, and is even more common than a faulty switch.

Regarding valve lock, If everything seems to be in order, get a big ass jumper battery, hook it up, floor the gas pedal, and crank the motor for at least 20 seconds without interruption. If during that time you feel the motor start to fire continue cranking without interruption until it finally starts up. I would not crank it longer than about 45 seconds without interruption.

Obviously, this advice assumes you don't have major mechanical damage or some other undiagnosed problem. If you do, this procedure may make everything worse. There is a certain sound and feel to this condition, and obviously, I cannot be there to experience it and make that judgment.

 

[samm]

Re: m119 94 E420 no start

Actually, it sounds a little bit like what happens when carbon falls off the valves and sticks them open just as you are cranking. Some of the valves get stuck open, and then the oil pressure enters the lifters thereby taking up the space and holding some valves open. And in extremely rare cases, a sticking oil pressure relief valve in the oil pump will push some of the valves off of the valve seats just as the engine starts. In each scenario you get crank and engine start, immediately followed by engine stall and a weird sound on attempted restarts, as yours seems to be doing. However, that restart cranking speed will usually seem a little high, not a little low, as yours seems to sound. Maybe your battery is a little weak after restart attempts.

Everyone seems to have hit most of the basics, but I want to repeat that you check your battery terminals, most especially the small additional wires that are on the positive battery terminal for good condition and contact, etc. etc.

Make sure that while your key is in the run position, and while you were cranking that the row of warning bulbs at the bottom of the instrument panel stay illuminated. Ignition switches can develop poor contact on circuits other than the cranking circuit, then the combined voltage drop from cranking demand along with voltage drop in the switch can cause the other important circuits to be low on voltage while you are cranking. A common contact to experience this anomaly is the one that feeds the ignition system. Do you have spark coming from the coils? No spark could mean a faulty ignition switch. Unfortunately, sudden EZL death has the same symptoms, and is even more common than a faulty switch.

Regarding valve lock, If everything seems to be in order, get a big ass jumper battery, hook it up, floor the gas pedal, and crank the motor for at least 20 seconds without interruption. If during that time you feel the motor start to fire continue cranking without interruption until it finally starts up. I would not crank it longer than about 45 seconds without interruption.

Obviously, this advice assumes you don't have major mechanical damage or some other undiagnosed problem. If you do, this procedure may make everything worse. There is a certain sound and feel to this condition, and obviously, I cannot be there to experience it and make that judgment.

Well.......

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[samm]

Re: m119 94 E420 no start

I ran through it methodically.
Spark was found at the distributors.
Fuel was at a good pressure at the fuel rail. Came spraying out.

Could not check if camshafts are moving or not as I don't have anyone assisting.

BUT...

I am extremely upset to say that the compression looks like it's totally screwed.

I completely disconnected the EZL AND FUEL PUMP RELAY.

From the first Cylinder compression result I knew that what many of u have been saying is correct.

I only checked 5 out of the 8 cylinders but it was enough.

1 = 35psi
2 = 20 psi
3= 20 psi
4= 50 psi
5= 90 psi




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[Raffaelli]

Re: m119 94 E420 no start

Chain jumped or broke. Engines shelled.

 

[samm]

Re: m119 94 E420 no start

Bearing in mind I put a rebuilt transmission in it a few months ago I am extremely upset.

I have never owned a car in worse condition.

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[samm]

Re: m119 94 E420 no start

Can you guys please tell me what you think is wrong with my engine. Now you know the symptoms and the low compression. The fact that it ran roughly and then stalled.
Never to start again.
Battery is fully charged by the way.

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[samm]

Re: m119 94 E420 no start

By the way I have Mercedes 5w 30 fully synthetic oil in there. It has been consuming oil at a slightly high rate. I used to have 5w 40 fully synthetic before and it never used much at all.

Car was cold when I did the compression test because it doesn't start obviously

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[samm]

Re: m119 94 E420 no start

Chain jumped or broke. Engines shelled.

If you are right how on earth can the chain jump?
The tensioner or guide rails?

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[samm]

Re: m119 94 E420 no start

This the sound from the engine bay.
Spark and fuel are ok.

[video=youtube_share;yoixbHigeCM]

 

[gsxr]

Re: m119 94 E420 no start

This is REALLY bizarre. Are you certain you trust the compression gauge you are using?

The chain could theoretically jump if the upper guide rails are all broken along with a large helping of plain bad luck. I don't think I've ever heard of a report of a M119 timing chain jumping (nor breaking) on any of the MB forums. Maybe Klink has heard of it but it's gotta be bloody rare.

You can check camshaft timing (to verify the chain jumped) by removing at least one valve cover and seeing if the cams will pin at, or at least close to, 45° BTDC per the factory specs. Worn/broken rails may cause 5-8° of misalignment at the passenger exhaust cam. If it was 1 tooth off that would be 20° off at the balancer (i.e., ~25° BTDC), 2 teeth would be 40° off, etc. At this point you may want to pull one valve cover for additional diagnostics... I'd pull the passenger side since that is easier (don't need to disconnect any fuel hoses, nor the vac pipe to the brake booster). Be careful with the PCV hose at the rear, if it's fossilized, don't break it.

If the chain really has jumped, first thing is to reset all 4 cams to the correct timing per the manual, and replace any broken chain rails to prevent the chain from jumping again. You might get lucky and get it running again.

Worst case scenario is that valves were bent in which case you're looking at a replacement motor. Good news is you can source a used 4.2L motor pretty cheap (Jeff might have one for a few hundred bucks?), bad news is an engine swap isn't fun. I'd be very, very surprised if your motor really is toast...

 

[gsxr]

Re: m119 94 E420 no start

This the sound from the engine bay.
Spark and fuel are ok.

If that video was taken with all 8 spark plugs installed... that's not good. It does sound like a compression issue and your next check is camshaft timing after pulling valve cover(s).

 

[samm]

Re: m119 94 E420 no start

If that video was taken with all 8 spark plugs installed... that's not good. It does sound like a compression issue and your next check is camshaft timing after pulling valve cover(s).

Gsxr
If the cam timing is screwed then what are my options?
I really didn't hear any metallic noises. A couple of years ago I heard valves hitting pistons due to faulty timing in a V6 m272. But I didn't hear any metallic sounds when my engine stalled.

I just can't believe that my engine is finished.


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[samm]

Re: m119 94 E420 no start

This is REALLY bizarre. Are you certain you trust the compression gauge you are using?

The chain could theoretically jump if the upper guide rails are all broken along with a large helping of plain bad luck. I don't think I've ever heard of a report of a M119 timing chain jumping (nor breaking) on any of the MB forums. Maybe Klink has heard of it but it's gotta be bloody rare.

You can check camshaft timing (to verify the chain jumped) by removing at least one valve cover and seeing if the cams will pin at, or at least close to, 45° BTDC per the factory specs. Worn/broken rails may cause 5-8° of misalignment at the passenger exhaust cam. If it was 1 tooth off that would be 20° off at the balancer (i.e., ~25° BTDC), 2 teeth would be 40° off, etc. At this point you may want to pull one valve cover for additional diagnostics... I'd pull the passenger side since that is easier (don't need to disconnect any fuel hoses, nor the vac pipe to the brake booster). Be careful with the PCV hose at the rear, if it's fossilized, don't break it.

If the chain really has jumped, first thing is to reset all 4 cams to the correct timing per the manual, and replace any broken chain rails to prevent the chain from jumping again. You might get lucky and get it running again.

Worst case scenario is that valves were bent in which case you're looking at a replacement motor. Good news is you can source a used 4.2L motor pretty cheap (Jeff might have one for a few hundred bucks?), bad news is an engine swap isn't fun. I'd be very, very surprised if your motor really is toast...

Well I really appreciate your detailed response Gsxr. Dave.
I know it's all hypothetical at the moment.
I will remove the valve covers tomorrow. Start with the passenger side as you say.

Was it a 6mm bolt or so thing that is supposed to fit into the hole on the cams?

I didn't hear any metal hitting eachother.



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[samm]

Re: m119 94 E420 no start

I did not open the trottle. I just disconnected ezl and fuel relay. Plugged in the compression kit in each spark plug hole one at a time.
All spark plugs were kept in their holes, except for the cylinder I was testing.

I'm thinking I did it correctly. Cranked for 6 seconds per cylinder. Dry not wet.

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[Klink]

Re: m119 94 E420 no start

OK, at this point you have little to lose. If you have not already done so, you need to do the big ass battery/jumpstart crank at full throttle for AT LEAST 20 seconds continuously and see if it starts to light off. Remember, your compression readings will be bad if your valves have been pumped open. Only repeated compression by the camshafts will re-compress the lifters until the valves seat.
I have only ever seen chains break or jump on the early KE injection M119 which uses a different block and a different chain arrangement.
I have seen the lifter extension syndrome that I am describing countless times on all M119s.

 

[samm]

Re: m119 94 E420 no start

OK, at this point you have little to lose. If you have not already done so, you need to do the big ass battery/jumpstart crank at full throttle for AT LEAST 20 seconds continuously and see if it starts to light off. Remember, your compression readings will be bad if your valves have been pumped open. Only repeated compression by the camshafts will re-compress the lifters until the valves seat.
I have only ever seen chains break or jump on the early KE injection M119 which uses a different block and a different chain arrangement.
I have seen the lifter extension syndrome that I am describing countless times on all M119s.

Klink
Can you let me know why I need to floor the accelerator?


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