w140-more problems

[kth286]

before replacing all and sundry why not just get the trouble codes read by a specialist that is used to your car type and has the experience of the codes.

 

[r129co]

JIB is right. Diagnostics cant read a sensor that is out of the loop so to speak i.e lost its connection.
I have heard Television mention this before and I have had two 119s with misfires caused by coils that were either wet or had poor earths.
Does nobody go out in the dark and stick their head in the engine bay with the motor running anymore.Close the bonnet down on your self and watch St Elmoes fire...tells you some hot spots!
Carl

I have what you need so you dont need to know what I have....but I do have to know what you need .

 

[television]

JIB is right. Diagnostics cant read a sensor that is out of the loop so to speak i.e lost its connection.
I have heard Television mention this before and I have had two 119s with misfires caused by coils that were either wet or had poor earths.
Does nobody go out in the dark and stick their head in the engine bay with the motor running anymore.Close the bonnet down on your self and watch St Elmoes fire...tells you some hot spots!
Carl

I have what you need so you dont need to know what I have....but I do have to know what you need .

That was something that we did years ago We just tell the odd one now

 

[r129co]

Tell the odd what Malcolm?

 

[television]

Tell the odd what Malcolm?

We do not get so many cars where the spark display gives a problem,, it is only on the early cars,

 

[sully]

ive got no further with it yet. just back from edition38 show and still suffering!
i have already checked for fireworks! all leads seem ok and each cylinder is getting a spark. and 2 new coils also fitted tho will check to 2 connections to them.
is the crank sensor on these the same as the flywheel pick up?

 

[sully]

update - new flywheel position sensor purchase at £125. no change! dissconnected lamda to see if would run in default mode - no change.

bugger!

 

[Alex Crow]

the rotor arms on these engines can give major headaches. the pattern ones are not worth a fig, we never use any pattern rotor arms or caps btw - not worth the hassle.

 

[jibcl500]

EZL or ignition control module must be your next point to check.

jib

 

[sully]

whats a EZL? in betting that both of these items are goin to hurt my wallet!

might give genuine rotor arms ago. the caps a fitted where bosch items which should be the same as oem. i hope!

 

[television]

EZL ECU's cost bosch £4 to have made and they sell them for £1200

 

[shane10010]

Hi Sully and team,

Like many I too have spent many hours on the various forums trying to test parts and diagnose my problem and I wonder if it is the same as / similar to yours.

Symptoms:
- Hesitation under light acceleration (2000rpm)
- Engine stalls when hot and will only restart 15-20 mins later

Replaced so far (with new original MB):
- Engine Wiring Harness - insulation degraded
- ETA - insulation degraded
- Fuel Filter - good practice
- Distributor caps & Rotors
- Spark plugs - NGK
- Crankshaft Position Sensor - heavily corroded and wiring stiff - New part arrives tomorrow. Connects to the Ignition Control Module

Considering / Considered:
- MAF - no difference if disconnected
- Coils - One behing headlight looks corroded
- Plug & Coil Leads

It was at the suggestion of a breakers yard that I am now investigating the symptoms of a faulty EZL / Ignition Control Unit.
Can anyone advise the symptoms of a faulty EZL? There is a suggestion that it either works or it doesn't.

Any guidence welcome.
Shane

 

[Autofix]

With a problem like this the first thing you need to do is to figure out if the problem is ignition or fuel. Serial diagnostics, while worthwhile, is a little lacking on these. The right tool for the job is an oscilloscope being driven by someone who actually knows how to use it.
As already stated, caps, rotors and leads give endless trouble on these and cheap ones do not work. I have scoped brand new cheap ones and found them faulty out of the box. Bosch all the way.
The looms on the V8’s didn’t give as much trouble as the V12’s. One weak point on the looms was at the temp senders. This can be checked in live data serially.
No body has mentioned fuel pressure yet, worth checking.
Blocked exhaust is also possible.

Considering the amount already spent on “bolt on diagnostics” a few hours quality diagnostic time might be a good investment. Better to test than guess.

 

[sully]

yeah them seem like the same problems as mine. i have a guy that works in mercedes and apparently is good at electrical problems coming over 2moro nite with all the test gear so i hope he can find out the source of the problem and will pass on any info to you guys.

just out of interest, where is the ezl and ignition control module located on these wagons.

just want it fixed!!

 

[wright]

well? is it fixed?