1993 400e rescue

[natejgreene9871]

So, after about 3 years of lurking on this website and looking for a good project 400e, I finally found one. I wanted a pre-facelift which has been hard to find.


I found it about 30 minutes from my house in Nashville, out in the country. On Facebook Marktplace. The ignition tumbler was totally locked up and the previous owner had given up and abandoned it for about a year. Today I tried for hours to get the key to turn but ended up drilling it out. Major project.







Car has 138,000 miles, good original paint no peeling, recently installed rebuilt transmission from Sun Valley Mercedes. Interior wood & seats are nice, headliner sagging a bit. AC works. Zero rust southern car.

I probably overpaid a bit at $3,300 but I really, really wanted this car. Surprisingly lots of competition from other buyers, I had to be very aggressive.




So I drilled out the steering lock, bypassed the neutral safety switch and alarm immobilizer. Car will run if you hold down the throttle but chokes and dies at idle. Upper and lower harness have been replaced but I do not think the ETA has. Any ideas how I can limp this car 30 minutes home with a bad ETA? I'd rather not pay for a tow truck but also don't want to fry the ECU. Will the car run if I just unplug the ETA? Non ASR car.

Any ideas on getting it home and do you think I overpaid?

 

[gsxr]

Congrats on the score! The price was a little high for a locked tumbler and non-drivable, but the unusually nice condition makes up for it.

Since it's a non-ASR car, a bad ETA should only affect idle & cruise control, when you press on the gas it should drive ok. What happens when you try to drive it? Does it bog & die? Will it not idle unless you hold your foot on the pedal? Any warning lights on?

 

[winmutt]

Get a code blinker and see whats reported. Check for vac leaks and distributors

 

[natejgreene9871]

Congrats on the score! The price was a little high for a locked tumbler and non-drivable, but the unusually nice condition makes up for it.

Since it's a non-ASR car, a bad ETA should only affect idle & cruise control, when you press on the gas it should drive ok. What happens when you try to drive it? Does it bog & die? Will it not idle unless you hold your foot on the pedal? Any warning lights on?

yes, when I give it gas it drives away/revs freely and has good power. Doesn't hesitate. Just wont idle. I have to hold it at higher rpm. No dash lights

 

[gsxr]

yes, when I give it gas it drives away/revs freely and has good power. Doesn't hesitate. Just wont idle. I have to hold it at higher rpm. No dash lights

Sounds like it's drivable then? When you have to stop, keep your foot on the gas to keep it from dying.

Check ALL fuses, including the GM-style blade fuses in the BM/GM module inside the CAN box. I'm guessing the T/LLR module is not properly controlling the ETA for idle speed. As a short term fix you could also try adjusting the throttle cable behind the airbox to maintain a high idle (note this does NOT work for models with ASR, it will trigger limp mode).

After you get it home, definitely need to pull codes from all modules. If you don't have a hand-held blink code reader, you'll need to buy or make one. See the "De-Coding" subforum for details. This 400E is a very different beast compared to your other cars.

 

[natejgreene9871]

Sounds like it's drivable then? When you have to stop, keep your foot on the gas to keep it from dying.

Check ALL fuses, including the GM-style blade fuses in the BM/GM module inside the CAN box. I'm guessing the T/LLR module is not properly controlling the ETA for idle speed. As a short term fix you could also try adjusting the throttle cable behind the airbox to maintain a high idle (note this does NOT work for models with ASR, it will trigger limp mode).

After you get it home, definitely need to pull codes from all modules. If you don't have a hand-held blink code reader, you'll need to buy or make one. See the "De-Coding" subforum for details. This 400E is a very different beast compared to your other cars.

I'm just afraid that i will short something out trying to drive it. If the ETA wires are all touching wont i burn up the ECU or some control module?

I have a handheld blinker. Hoping that will be sufficient, an SDS is expensive.

 

[gsxr]

I'm just afraid that i will short something out trying to drive it. If the ETA wires are all touching wont i burn up the ECU or some control module?

It's unlikely anything will be damaged during a 30-minute drive. If the ETA wiring is bad, you'll need to repair the wiring, or replace with a late-datecode, non-ASR ETA (from either 124 or 140 chassis). It's also possible the T/LLR module is defective, but not likely... they are relatively inexpensive used if needed. Once you get it running, it would be a good idea to obtain a spare of each of the 5 control modules for spares and future diagnostics.

I have a handheld blinker. Hoping that will be sufficient, an SDS is expensive.

The blinker box will work for basic diagnostics. For really difficult problems, the live data from SDS can be very useful, but worry about that if/when you need it. Probably ~$750 all-in for a C4 SDS including laptop and software that supports HHT-Win.

 

[a777fan]

@gsxr and others will chime in, but these things have been going for years with this junk wiring. V unlikely the drive home will burn out the ecu.

Congrats on the pickup!

 

[natejgreene9871]

also this radiator fitting has failed and coolant is leaking out. I thought about JB welding it but I don't think it will work.

I've ordered one but wont be here for several days

 

[gsxr]

also this radiator fitting has failed and coolant is leaking out. I thought about JB welding it but I don't think it will work.

I've ordered one but wont be here for several days

You can drive with the radiator cap loose, to prevent pressure from building, for the 30-minute trip home. As long as temps stay under 100C (unmarked line on the gauge), it should be fine.

 

[sheward]

I think it was a good purchase. Very hard to find an 034 in that condition for that money.

I have both an ETA and TLLR module for a non ASR car should you need.

 

[natejgreene9871]

Had the car towed home today and I have been poking around under the hood. The throttle body sticker says 1992 however I cut the wiring open and it looks ok. The plug says "02" on it.

Perhaps this throttle body has been rebuilt??

So, now I'm wondering what the real issue is.

I have ordered new distributor caps, could it really be that simple?

When I can get it running, it seems to be running very rich.

Next step will be code blinker i guess..

 

[gsxr]

Blinker box will help, but if by "running rich" you smell gas, something else may be going on.

What was wrong with the existing caps (or rotors)? Did you remove the rotor bracket to inspect the back side of the insulator for liquid, and to verify the cam oil seal isn't leaking, which can cause misfiring problems? Lots of old threads on the forum discussing all of this, but it's primarily related to misfiring, and so far you haven't specifically mentioned misfiring.

Be careful what brand of caps / rotors you buy. There's junk out there, don't buy based on price...

 

[natejgreene9871]

oh wow this could have something to do with it….

Ordered 2 new Bosch ones online outch$$$

 

[gsxr]

Bosch caps are OK. If you buy rotors, OE/Genuine are preferred but they are twice the price of Bosch. Avoid Bremi or other brands.

Your caps show traces of arcing (the black lines) which may be related to the wet appearance. You'll need to figure out if that is moisture / condensation, or if it's related to oil leaks at the cam seal and/or intake cam solenoid. Next is to pull the insulators and check the back side. Fix oil leaks before installing the new parts...

 

[natejgreene9871]

Good info thank you very much.
Another strange issue I noticed is that some of the backlights in the interior stay on. For example, the window switches, gear shifter. it’s draining the battery.

Dome light works correctly and shuts off automatically.

Could be a bad headlight switch?

 

[gsxr]

That does seem like a bad headlight switch. Fiddle with the positions and see if the interior lights go off. Also make sure there is a clean, positive "click" into each detent. If not... definitely get a new switch. OE/Genuine only, not expensive, not difficult to replace either.

 

[natejgreene9871]

Finally got all of my parts in the mail to get this car moving this afternoon.

And then I got to the distributor rotors..... What a piece of fucking shit design. I swear this is not the MB I know.


Screws are impossible to remove, stripped out, I busted the rotor bracket trying to hammer in a torx bit. Had to dremel them

Going to have to order a new bracket, of course unobtainable anywhere locally.

Even the brand new bosch rotors the screws wanted to strip as I was installing them.

 

[a777fan]

I think the rotor bracket is NLA, which means ebay will be your bff.

When installing those rotors you have to be sure to always always fully insert the allen head into the bolt before applying any pressure. You’ll likely hear a little ‘click’ as the head bottoms out in the bolt.

Sometimes however, depending on the make of the rotor, the quality of the bolts themselves can vary. Additionally, the bolts can degrade with time/use, making it more difficult to fully seat the allen head in the bolt, both of which may have meant you might have been screwed before you even started disassembly.

 

[asultan]

Finally got all of my parts in the mail to get this car moving this afternoon.

And then I got to the distributor rotors..... What a piece of fucking shit design. I swear this is not the MB I know.


Screws are impossible to remove, stripped out, I busted the rotor bracket trying to hammer in a torx bit. Had to dremel them

Going to have to order a new bracket, of course unobtainable anywhere locally.

Even the brand new bosch rotors the screws wanted to strip as I was installing them.

View attachment 173257
View attachment 173258

On reassembly go just a hair over finger tight, pretty sure the spec here is like 3nm...

 

[sheward]

I do believe I have a bracket for you. I'll let you know tomorrow. I can put it in the mail Monday. We are close. There's much discussion here about the issue you've "discovered"

 

[gsxr]

Screws are impossible to remove, stripped out, I busted the rotor bracket trying to hammer in a torx bit. Had to dremel them

Yeah... if they strip, you're in trouble.

Going to have to order a new bracket, of course unobtainable anywhere locally.

THey are NLA new, have to get used ones from eBay or a forum member.

Even the brand new bosch rotors the screws wanted to strip as I was installing them.

Bosch rotors use funky bolts which NO Allen wrench fits into snugly. This is another reason I prefer the Genuine MB rotors made by Doduco, because the bolts aren't junk, and a 3mm Allen fits properly. But, they cost 3x vs Bosch rotors. You can install aftermarket bolts to cure this problem, search the forum for details.

While it's apart, remove the bracket & insulator and check the cam seal back there for leakage. If not bone dry, replace the seals. The insulators may also need replacement. Use a tiny dab of blue threadlock on both the rotor bracket (single center bolt) and the 3 little bolts for the rotor as well. If these loosen & back out, they destroy everything.

 

[Gatorblue92]

Not a good idea nor do I recommend but one of my prior 93 400Es was running for who knows how long with one of those ears broken off the distributor bracket. I sourced a replacement when I did that job but it had been running for some unknown amount of time prior to my purchase.

 

[natejgreene9871]

Based on gator's message, I went ahead and screwed it back together. It is working fine for just idling in the driveway. Part on the way.

Car is running better but still not right. Sounds good and smooth at higher RPM's but tends to die at idle.

I checked diagnostic codes using a blinker. I ran the initial codes, and then reset them all and ran the car again. Two codes came back immediately (highlighted yellow):





I'm not sure I am reading pin #7 correctly?? See below excerpt:





So, in summary I have recurring codes:

• 6 on PIN #7
• 6 on PIN #17

Where do I go from here?

Thanks,
Nate

 

[gsxr]

Defective CMP sensor needs investigation. This is the cam position sensor located just inboard of the driver side intake cam solenoid. Make sure the (round coaxial) connector is fully seated. Check if the sensor is original or has been replaced with aftermarket. If the upper harness has been replaced, the wiring should be ok between module and CMP sensor.

I'm not sure about code 6 on pin 7. The blink code is the left column, single digit... "not valid for USA vehicles". You can't obtain the 3-digit digital codes without SDS / HHT-Win.

 

[natejgreene9871]

Making progress!!!

I didn't know what else to do so I installed the rebuilt throttle body I bought on ebay. Those clamps are a bitch to remove.

It made a huge difference!

Idling great & very quiet, I drove it around the block for its maiden voyage and it did really well. No stalling at all.

Still a little hard to start for some reason, cranks longer than I would like. But once it is running it is doing pretty good. I'd say i'm 90% of the way there.

Once I get the rotor bracket replaced I'll be able to go for a real drive and re-evaluate my codes. Hopefully the code 6 on pin #7 will go away.

For the CMP sensor I don't know. All wiring harnesses on this car have been replaced. I reseated the coax cable and saw no physical signs of any type of damage.

Moral of story, even if your TBA has good wiring and buzzes, it may still be broken..

 

[gsxr]

Nice! What vendor did you buy the rebuilt ETA from on eBay?

 

[natejgreene9871]

Nice! What vendor did you buy the rebuilt ETA from on eBay?

sfarooqa

MERCEDES THROTTLE BODY 000 141 78 25 (0001417825) (FULLY TESTED) Core Refund $90 | eBay

Find many great new & used options and get the best deals for MERCEDES THROTTLE BODY 000 141 78 25 (0001417825) (FULLY TESTED) Core Refund $90 at the best online prices at eBay! Free shipping for many products!

www.ebay.com

No idea on reputation, but quality seems pretty decent.

 

[natejgreene9871]

I must say, I think I spoke too soon. I'm definitely not out of the woods.


Something is going on with the EZL vacuum line.

 

[natejgreene9871]

I accidentally broke the vacuum line going to the ezl last night when replacing the throttle body. This is what made the car run correctly. Once I fixed the hardline tonight, it started running bad again.

Car runs like crap with EZL vacuum line plugged in, runs good with it unplugged. What the hell does this mean?

Here is a video, running both ways.

This thread makes me think it could be a T/LLR issue? But I don't understand how the EZl vacuum advance would be related to the T/LLR?

Other than that, could it be a bad EZL ?

Idle Surging | M119 Engine

Hi, Searching for some sage advice. The '95 E420 I've had has developed a surging/high idle. To get a perspective, it has had: Fuel Pumps, FPR (Bosch units); Wiring harness replaced by PO; Thermostat and temp sending unit; All new ignition system, including...

www.500eboard.co

 

[gsxr]

Something is definitely weird. Live data from SDS / HHT-Win would be helpful here. If you had access to another EZL, I'd try swapping it to see if anything changes. With only the vacuum line on / off, the engine should not die, or have any significant change in running other than a small blip in RPM's when the hose is on/off. This should not be related to the T/LLR (although if you have a spare, swap it for grins).

Another long shot is something up with the LH module, as it seems there's an issue with fuel mixture... what part # is your LH module? Your EZL p/n appears correct for a 1993.

 

[gsxr]

Wait - have you fixed the cam position sensor fault yet? That should be resolved first!

 

[natejgreene9871]

Wait - have you fixed the cam position sensor fault yet? That should be resolved first!

I have a new sensor on order, will try that when it arrives

 

[gsxr]

I have a new sensor on order, will try that when it arrives

If that does the trick, try to get a used OE sensor from a junkyard, or buy a good used one (OE only). These are NLA from MB and the aftermarket ones may have a short lifespan. The originals are pretty rare failures. I'd also measure the resistance of old vs new for grins while you're in there...

 

[natejgreene9871]

Good advice, these are the modules I currently have, sticker on the ll/r looks more faded, possibly replaced before?

 

[gsxr]

The part numbers all look correct. The ABS module has been replaced previously, note the 1996 date code. The faded label could just be different paper vs the others, the date code matches the LH module.

 

[natejgreene9871]

I swapped the cam position sensor from my 300e and it made no difference. Resistance values were similar ish on the multimeter.

What now? I’m out of ideas.

 

[gsxr]

Does your 300E have an M104? If so, and there was no difference... did you still get the fault code returning with the different sensor? That would point to bad wiring or something up with the LH module which receives the signal from the CMP.

Edit: See post #41 below. The LH receives an indirect CMP signal. The CMP connects directly to the EZL.

 

[natejgreene9871]

Does your 300E have an M104? If so, and there was no difference... did you still get the fault code returning with the different sensor? That would point to bad wiring or something up with the LH module which receives the signal from the CMP.

Yes it is a 1993 with the m104. Same exact sensor and year. I haven’t checked codes again I will do that. So the cam sensor plugs into the LH module? All the wiring looks perfect, I cant find any bio wiring.

Again the engine won’t run at all with the cam sensor unplugged so it IS doing something even if it is throwing a code.

Seems like it has to be one of the following:

• LH module
• T/LLR
• EZL

 

[natejgreene9871]

I hooked everything back up correctly, I have the known good cam sensor installed, EZL vacuum line connected.

I ran the car 5 consecutive times, each time for a minute or so. Each time I let it stall out and checked codes on pins 4 (LH Module), 7 (T/LLR) , and 17 (EZL) and then cleared them.

Here are the results:

• Initial codes​

• LH Mod: 8
• TLLR: 6
• EZL: 6, 18

• Run one
• LH Mod: clear
• TLLR: clear
• EZL: 6

• Run two
• LH Mod: clear
• TLLR: clear
• EZL: 6

• Run three
• LH Mod: clear
• TLLR: clear
• EZL: clear

• Run four
• LH Mod: clear
• TLLR: clear
• EZL: 6, 18

• Run five
• LH Mod: clear
• TLLR: clear
• EZL: 6

So, in summary

1. Consistently getting EZL: CMP sensor (L5/1) defective
2. Occasionally getting EZL: Magnets for CKP sensor (L5) not recognized

Initial codes showed
LH mod : CMP sensor (L5/1) signal, open/short circuit
TLLR: Not valid for USA vehicles


Just to confirm, the cam sensor plugs into the LH module, NOT into the EZL ?

So why would the EZL show a code for cam sensor, if the cam sensor isn't even connected to it?

 

[gsxr]

Just to confirm, the cam sensor plugs into the LH module, NOT into the EZL ?

So why would the EZL show a code for cam sensor, if the cam sensor isn't even connected to it?

The FSM diagrams for the LH indicated a CMP signal connected to the LH module, but I looked up the schematics and those show L5/1 directly connecting to the EZL, connector B, pins 1 and 5. You can check for continuity between the L5/1 connector, and those 2 pins at the EZL. If that checks out OK, my guess is the EZL miiiight be faulty. If so, that would be a new EZL failure mode, I've not heard of this happening before. Usually an EZL failure results in one distributor/coil not firing, or both not firing (no-start condition). I've seen a faulty pressure sensor (inside the EZL) once.

The LH module DOES receive a CMP signal, but it's an OUTPUT from the EZL to the LH module - there is no direct connection between CMP and LH. The CMP connects to the EZL first. Sorry about the confusion!


See FSM job 15-0200, page 17 for the EZL pinouts.

And, see schematic 07-5.00/II (124.04-5.00/II) located here.

The LH pinouts are here.


In the meantime, put the M119 CMP into the 300E and verify the 300E runs normally. If so, you've definitely ruled out a faulty CMP sensor.

 

[natejgreene9871]

The FSM diagrams for the LH indicated a CMP signal connected to the LH module, but I looked up the schematics and those show L5/1 directly connecting to the EZL, connector B, pins 1 and 5. You can check for continuity between the L5/1 connector, and those 2 pins at the EZL. If that checks out OK, my guess is the EZL miiiight be faulty. If so, that would be a new EZL failure mode, I've not heard of this happening before. Usually an EZL failure results in one distributor/coil not firing, or both not firing (no-start condition). I've seen a faulty pressure sensor once.

The LH module DOES receive a CMP signal, but it's an OUTPUT from the EZL to the LH module - there is no direct connection between CMP and LH. The CMP connects to the EZL first. Sorry about the confusion!


See FSM job 15-0200, page 17 for the EZL pinouts.

And, see schematic 07-5.00/II (124.04-5.00/II) located here.

The LH pinouts are here.


In the meantime, put the M119 CMP into the 300E and verify the 300E runs normally. If so, you've definitely ruled out a faulty CMP sensor.

This is really helpful thank you

 

[natejgreene9871]

I ordered a used EZL and LH module on eBay. Was about $200 total. Hopefully they work. I’ll do some more testing later today.

 

[natejgreene9871]

Continuity from CMP coax plug back to EZL input confirmed as good, both wires.

 

[natejgreene9871]

I also verified continuity is good from output of EZL (plug A pin 8) to PIN 6 of LH module.

So, I'm not dealing with a wiring issue here. It has to be either a faulty EZL or LH module.

 

[natejgreene9871]

Opened up the LH module. I didn’t have the correct torx to separate the boards but I can see caps inside. I don’t see any bulging but I can’t imagine they are are all perfect after 30 years.

Seems like all of these modules will have to be recapped eventually, just a matter of time.

 

[natejgreene9871]

Used LH module arrived this morning. Installed it and no difference at all. Exact same behavior.

EZL hopefully arrive next week..

 

[natejgreene9871]

Anything else I should order for the parts cannon?

 

[natejgreene9871]

I’ve hit a dead end here. I have a friend that hoards MB parts and went to his house. Got the motherload.


Spare T/LLR, Base module, LH with WOT, EZL. Swapped it all in.

Still have the exact same behavior. No improvement. I haven’t scanned if the cam code is still there. Too frustrated to look at this thing anymore.

Any additional ideas? This car is turning out to be quite the money pit. Seriously out of ideas.

 

[gsxr]

Time for a refresh on current status. What codes return immediately, and what are the current symptoms / problems?

Last I saw was this: "Car runs like crap with EZL vacuum line plugged in, runs good with it unplugged. What the hell does this mean?"

Next would be verifying that each vacuum line is routed to the correct port on the intake manifold, there are 3 different vac ports, each has a specific function.