M119 runs poorly, wet spark plugs

[JC220]

I have never heard it runs properly, this car had been sitting for a long time.

Suggest not trying to start it any more until cam covers have been off and all engine timing checked and correct. I fear it may have slipped the chain on a sprocket.

M119s generally are reliable engines as what can be said of all petrol MB engines of the era. There is some deeper reason why yours is not firing up and running correctly. If you have spark, fuel and compression it should fire up at least. Appears like engine is off timing to me also listening to your video I think it doesn't sound normal.

 

[frall]

Are the ignition cables in the correct order?
If this is the case, you should check, that the timing is correct.

 

[Svein R]

Suggest not trying to start it any more until cam covers have been off and all engine timing checked and correct. I fear it may have slipped the chain on a sprocket.

M119s generally are reliable engines as what can be said of all petrol MB engines of the era. There is some deeper reason why yours is not firing up and running correctly. If you have spark, fuel and compression it should fire up at least. Appears like engine is off timing to me also listening to your video I think it doesn't sound normal.

I will check my compression today.

 

[Svein R]

Are the ignition cables in the correct order?
If this is the case, you should check, that the timing is correct.

Do you have a good form that shows where the plug cables should sit?

 

[frall]

 

[JC220]

I will check my compression today.

You need to confirm engine timing marks. Not a compression check.

 

[Svein R]

Are the ignition cables in the correct order?
If this is the case, you should check, that the timing is correct.

Do you have a good form that shows where the plug cables should sit

View attachment 143380

Thanx

 

[Svein R]

Maybe you have a good form which shows the cam timing marks as well?

 

[kubasz]

Hi guys
I was recently having E420 with exackly the same situation. No start with the fuel and spark being delivered on time. Wet spark plugs etc. After two weeks of checking everything i pulled the o2 sensor and the engine started right away. Clogged cat was the problem

 

[JC220]

Maybe you have a good form which shows the cam timing marks as well?

I'm on my phone only today- lots of posts and threads on engine timing just use the forums search function

 

[Svein R]

Hi guys
I was recently having E420 with exackly the same situation. No start with the fuel and spark being delivered on time. Wet spark plugs etc. After two weeks of checking everything i pulled the o2 sensor and the engine started right away. Clogged cat was the problem

The cat on this car was replaced 4 years ago, it’s been sitting since.

 

[gsxr]

Wire routing is marked in the bottom of the plastic tray, look closely with a flashlight.

To check cam timing you need to remove both valve covers, pin 1 cam at a time, and read the crank indicator. And, check the plastic guide rails while the valve covers are off. I'd try easier things first.

 

[Svein R]

Did you verify fuel injector wire signal pulse too?

And as Gerry says that all ignition cables are correctly routed.

I have checked and the injector pulse signal was good, also checked with my strop light and every cable blinks

 

[Svein R]

How will a faulty O2 sensor affect my problem? Could that be my problem with soaking wet spark plugs?

 

[gsxr]

How will a faulty O2 sensor affect my problem? Could that be my problem with soaking wet spark plugs?

It's a long shot, but it's easy & free to disconnect the O2 sensor and see if there is any difference.

 

[JC220]

@Svein R I noticed this code in another thread of yours posted yesterday



Does this camshaft sensor code return when cleared each time you try to start the car?

If so , again - check engine timing.

Please also clear all trouble codes. Then try to start car and provide a list of any trouble code(s) that re appear. Interested to see if the EZL also holds any additonal codes which it may do in connection with the camshaft sensor fault code.

Note that the camshaft sensor fault code in itself will not prevent the engine from starting. But could be an indicator the engine timing is off. Need to know if the EZL has any crank sensor codes too in which case the code 008 could be a result of.

 

[JC220]

Quoting @gsxr here from another thread:

Have you confirmed the camshafts are timed correctly? That would be my first check. Rotate the crank to 45° BTDC and see if both cams will pin. If not, rotate the crank 1° at a time (44°, then 43°, 42, etc) until each will pin. If they are off a little (say, less than 10° at the crank) that shouldn't cause the fault codes (or lack of power) you are experiencing. But if it's 20° or more, it must be fixed. One tooth on the chain/sprocket is 20° at the crank.

FSM link:

https://freescruz.com/.priv/W124/w124CD1/Program/Engine/119/05-2230.pdf

View attachment 129274

 

[Svein R]

@Svein R I noticed this code in another thread of yours posted yesterday

View attachment 143411

Does this camshaft sensor code return when cleared each time you try to start the car?

If so , again - check engine timing.

Please also clear all trouble codes. Then try to start car and provide a list of any trouble code(s) that re appear. Interested to see if the EZL also holds any additonal codes which it may do in connection with the camshaft sensor fault code.

Note that the camshaft sensor fault code in itself will not prevent the engine from starting. But could be an indicator the engine timing is off. Need to know if the EZL has any crank sensor codes too in which case the code 008 could be a result of.

The camshaft code only came up once, but the engine won’t start now so maybe that’s why? I will pull my cam covers and check my timing today.

 

[Svein R]

@Svein R I noticed this code in another thread of yours posted yesterday

View attachment 143411

Does this camshaft sensor code return when cleared each time you try to start the car?

If so , again - check engine timing.

Please also clear all trouble codes. Then try to start car and provide a list of any trouble code(s) that re appear. Interested to see if the EZL also holds any additonal codes which it may do in connection with the camshaft sensor fault code.

Note that the camshaft sensor fault code in itself will not prevent the engine from starting. But could be an indicator the engine timing is off. Need to know if the EZL has any crank sensor codes too in which case the code 008 could be a result of.

I checked my timing chain yesterday and the result was not very good. When I had locked locked the camshafts with bolts, it turned out that the timing was many degrees wrong. I attach a photo I took

 

[Svein R]

You need to confirm engine timing marks. Not a compression check.

The compression was 150psi all over

 

[Svein R]

I checked my timing chain yesterday and the result was not very good. When I had locked locked the camshafts with bolts, it turned out that the timing was many degrees wrong. I attach a photo I tookView attachment 143447

 

[Svein R]

I forgot to mention that one of the cam sliders was broken off

 

[JC220]

I checked my timing chain yesterday and the result was not very good. When I had locked locked the camshafts with bolts, it turned out that the timing was many degrees wrong. I attach a photo I tookView attachment 143447

I forgot to mention that one of the cam sliders was broken off

OK I thought that may have been the case- however at least you've found the likely reason why it won't start so that's good!

The next thing to do would be renew both sets of upper timing rails complete and see how the timing marks line up then. The chain could also be stretched a little but initially I'd want to confirm the engine runs OK with the upper rails replaced. It might have bent valve(s) But don't worry about that just now until upper guides corrected chances are it's fine.

If it did misfire after getting timing right then a leak down test would be the way to check for engine damage - bent valves etc.

But my gut tells me you will be fine once timing corrected.

 

[Svein R]

I’ve already ordered both chain and guid sleeves, is it easy to replace the chain or do I remove all camshafts?

 

[JC220]

I’ve already ordered both chain and guid sleeves, is it easy to replace the chain or do I remove all camshafts?

I would start with the upper guides and re check timing. The chain could be AOK and it would add alot of cost and time time the project to renew the chain. Really I would take the engine out and re seal covers, replace all guides etc if replacing the chain.

Important note: DO inspect the other upper chain guides situated either side of the chain within the depth of the cylinder heads. It is common for these to break also!! Items 8, 14 & 26 in the diagram below.



There is a good video series on m119 chain replacement in car below if you want to watch

Here is also a link to upper guide replacement here:

Post in thread 'RESTO PROJECT: M119 / W124 / E500 Engine Top-End Refresh' RESTO PROJECT: M119 / W124 / E500 Engine Top-End Refresh | Member Roadtrips and Project Journals

 

[Svein R]

I would start with the upper guides and re check timing. The chain could be AOK and it would add alot of cost and time time the project to renew the chain. Really I would take the engine out and re seal covers, replace all guides etc if replacing the chain.

Important note: DO inspect the other upper chain guides situated either side of the chain within the depth of the cylinder heads. It is common for these to break also!! Items 8, 14 & 26 in the diagram below.

View attachment 143448

There is a good video series on m119 chain replacement in car below if you want to watch

Here is also a link to upper guide replacement here:

Post in thread 'RESTO PROJECT: M119 / W124 / E500 Engine Top-End Refresh' RESTO PROJECT: M119 / W124 / E500 Engine Top-End Refresh | Member Roadtrips and Project Journals

I will follow your advise, thanks for good helping

 

[JC220]

Here is another no start m119 video actually. Probably just like yours.

take a look about halfway into the video - he shows the guides I am talking about. I would almost guarantee yours are also broken.

 

[JC220]

An example of the same guides in one of my m119s



For other reasons that particular job grew out of control

 

[gerryvz]

An example of the same guides in one of my m119s

View attachment 143449View attachment 143450View attachment 143451View attachment 143452

For other reasons that particular job grew out of control

View attachment 143453View attachment 143454

I found the same exact thing when I removed the guide on my car. 143,000 miles, and the engine has been VERY well taken care of.

Photos here.


Here's the difference between a broken upper guide and one that is not broken (same chain).

 

[gsxr]

The photo showing the timing appears to be ~10° off at the crank? If so, that is not good and should be remedied, HOWEVER the engine should start & run just fine if it's only 10° off.

(I once bought a car that had 3 camshafts off by 20°, one tooth of the chain, and it ran just fine... but I fixed the cam timing anyway.)

 

[Svein R]

I found the same exact thing when I removed the guide on my car. 143,000 miles, and the engine has been VERY well taken care of.

Photos here.


Here's the difference between a broken upper guide and one that is not broken (same chain).

I found the same exact thing when I removed the guide on my car. 143,000 miles, and the engine has been VERY well taken care of.

Photos here.


Here's the difference between a broken upper guide and one that is not broken (same chain).

 

[Svein R]

So you mean that replacing the broken sliders will Get the cam timing perfect again? Then maybe I do not need to change the chain?

 

[gerryvz]

So you mean that replacing the broken sliders will Get the cam timing perfect again? Then maybe I do not need to change the chain?

No. But a broken slide will cause the timing to be "off" from 1-3 degrees (and it's possible a stretched chain will cause another 1-3 degrees -- but stretched chains are not a significant issue with the M119). If your timing is off by 10 degrees as your photo shows, there are other issues that you need to investigate and address. The process for documenting and determining the cam timing is in the factory service manual. Basically you need to move the engine to 45 degrees BTDC, and then see where your cams are at (with the pin holes in the back). That will tell you how "off" things are. You should be able to "pin" all four cams when the engine is at 45 degrees BTDC.

What JC220 and I were describing is that it is very very very common for the one upper chain rail to be broken. He and I both have found this, and many others here also have found this problem. It's usually the one rail that is the only one that breaks. But this isn't going to cause your timing to be off by 10 degrees. You have other issues.

 

[Svein R]

No. But a broken slide will cause the timing to be "off" from 1-3 degrees (and it's possible a stretched chain will cause another 1-3 degrees -- but stretched chains are not a significant issue with the M119). If your timing is off by 10 degrees as your photo shows, there are other issues that you need to investigate and address. The process for documenting and determining the cam timing is in the factory service manual. Basically you need to move the engine to 45 degrees BTDC, and then see where your cams are at (with the pin holes in the back). That will tell you how "off" things are. You should be able to "pin" all four cams when the engine is at 45 degrees BTDC.

What JC220 and I were describing is that it is very very very common for the one upper chain rail to be broken. He and I both have found this, and many others here also have found this problem. It's usually the one rail that is the only one that breaks. But this isn't going to cause your timing to be off by 10 degrees. You have other issues.

I have a wis / asra xentry diagnostic machine, assume that there is information there about the cause and what should be done in case of incorrect cam timing. Are you familiar with MB WIS?

 

[gsxr]

WIS (Workshop Information System) has all service info for most MB's from the early 1990's and newer. However, it has little if any additional information compared to the W124 CD-ROM service manual, which has all the M119 engine repair documents you need (click here, then click M119, etc).

The cause of incorrect cam timing ~10° or less is usually broken guide rails along with a small amount of chain stretch. The FSM / WIS implies that it is normal to have ±2° of "stretch", or timing error, with a used chain - particularly at the passenger exhaust cam. You'll only see perfect cam timing with a new chain and new rails, and new components do not guarantee zero deviation.

 

[maw1124]

WIS (Workshop Information System) has all service info for most MB's from the early 1990's and newer... The cause of incorrect cam timing ~10° or less is usually broken guide rails along with a small amount of chain stretch. The FSM / WIS implies that it is normal to have ±2° of "stretch", or timing error, with a used chain - particularly at the passenger exhaust cam. You'll only see perfect cam timing with a new chain and new rails…

maw

 

[Svein R]

Hello, I have a starting problem on my 92 SE500 W140. it just starts and runs poorly at idle, it smells of petrol and the spark plugs get completely wet. My Star tester with HHT-Win sets no codes at all. I have tested all my injectors and the are good, I have replaced all ignition parts and I have replaced all rubber and gaskets on my inlet manifold Do any of you have any views on this issue?

Hello guys, long time no see

I would try the following things:
1. engine start without MAF. If the engine runs ok, probably the MAF is defective. If not:
2. ignition on and moving the gas cable by hand until the ETA is electrically out of function.
3. Start the engine. If the engine will run ok, the ETA should be the problem.

I have tried both, no start. My spark plugs gets soaking wet.

 

[Svein R]

Ebay perhaps.

But can you make a video from inside (instruments) and from outside (engine) at the starting process.

 

[Svein R]

Did you verify fuel injector wire signal pulse too?

And as Gerry says that all ignition cables are correctly routed.

All 8 pulses great

 

[Svein R]

If all 8 plugs are firing, and the plugs are wet, and exhaust smells of fuel... the mixture is excessively rich. Need more data... any change if you disconnect the MAF? How old is the O2 sensor? Do you have a spare M119 LH module (any module / any displacement) for testing? Checked for vacuum leaks?

I have disconnected my o2 sensor but still no start

 

[Svein R]

Quoting @gsxr here from another thread:

I have replaced the camchain and two upper slides(which where broken) everything is perfect now

 

[Svein R]

No. But a broken slide will cause the timing to be "off" from 1-3 degrees (and it's possible a stretched chain will cause another 1-3 degrees -- but stretched chains are not a significant issue with the M119). If your timing is off by 10 degrees as your photo shows, there are other issues that you need to investigate and address. The process for documenting and determining the cam timing is in the factory service manual. Basically you need to move the engine to 45 degrees BTDC, and then see where your cams are at (with the pin holes in the back). That will tell you how "off" things are. You should be able to "pin" all four cams when the engine is at 45 degrees BTDC.

What JC220 and I were describing is that it is very very very common for the one upper chain rail to be broken. He and I both have found this, and many others here also have found this problem. It's usually the one rail that is the only one that breaks. But this isn't going to cause your timing to be off by 10 degrees. You have other issues.

I have replaced both broken sliders and repaced my chain, the cam timing is now perfect. But the engine still wont start

 

[Svein R]

Insulators behind the caps have been replaced?

The ignition wire routing has been double and triple checked en ensure that the correct wires are going to the correct cylinders?

I have replaced both insulators

 

[Svein R]

Ebay perhaps.

But can you make a video from inside (instruments) and from outside (engine) at the starting process.

 

[Svein R]

Ebay perhaps.

But can you make a video from inside (instruments) and from outside (engine) at the starting process.

 

[gsxr]

I have disconnected my o2 sensor but still no start

Try disconnecting the MAF, not the O2 sensor. MAF is below the air cleaner, above the ETA.