Hi guys,

What would be the symptoms of a failing Ignition control module?
Car is a 1990 190E 2.5-16 Auto...

Any Info would be great.

Thanks

Zak

Engine would be hard to start, stalling, or not start at all. Have you priced a new or used ICM lately?
Check the Crankshaft Position Sensor first. If it is open, dirty, or defective, it will give an indication of a faulty ICM.
You could also have a bad coil.

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1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

Hi SLK, thanks for the reply. No problems at all in starting the car and no stalling.
I have priced one up and to be honest the price is a disgrace to say the least.
The story is...
On WOT(wide open throttle) the car begins to hesitate/kangaroo back and forth, this is especially noticeable and worse when you use kick down.
Now, after going to many a specialist and after changing things like:

- Fuel distributor
- EHA valve
- All Injectors
- Fuel pressure regulator
- K-Jetronic ECU
- Fuel pumps
- Fuel pump relay
- Coolant temperature sensor
- Fuel accumulator
- Fuel filter
- Ignition leads
- Rotor arm
- Ignition coil
- Cold start valve
- Idle air valve
- Crankshaft position sensor

I finally gave the car into the main dealer. They have had it for six weeks and cannot work out the problem! Now they say they suspect it may be the ignition control module causing this hesitation. I understand that the ICM stores various ignition and load maps in its memory...

Any ideas or clues, because im stumped and so it seems is everyone else!

Hi Zak, you should keep your thread going on the other forum too, I added something then saw that you deleted it. There are some sharp W201 guys over there.

Wow, you've replaced quite a few expensive parts Zak. I hope the dealer can find the problem, if so, please post the resolution.

It would sure be a shame to have replaced all of those parts and find out that you have a bad ground connection!

I see that the EHA was replaced but I didn't see a Throttle Position Sensor on the parts list. Was is tested?

Dave

__________________

1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

I should have bought a Lexus! LOL

Well they say they tested everything, but lord only knows if its true or not...

The TPS has not been changed, but hey what the hell i'll change that too! Just kidding

But seriously...Its the weirdest problem i have ever come across.

In a way changing all those parts is a bit sickening...BUT, its preventative maintenance! LOL

Well they are going to put a new ICM in there. Lets see what happens after that!

Let's hope that will fix it. ICM=$$$$$$$$$

Good luck,

Dave

__________________

1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

I can get a new ICM for $900 or there abouts if it is that!
If it is that it will be good to finally know after all this time what the problem was!
Then i can save up and get one :-)

Hi Zakh,

The Ignition Control Module my M102 2.0 190E failed once.
Please refer to this rthread for the symptoms :

Newbie Needs Help

ThankYou cunix, i will take a look...
BTW i love Malaysia, really miss Penang! :-)

Ok, i read the thread...Sounds Interesting, although my car does not stall at all!...Im thinking SLK might have a point with the throttle position sensor.

This is what i found:

Engine Hesitation on Throttle Application: The TPS is also used by the ECU to determine if the driver has applied the throttle quicker than the Manifold Air Pressure sensor can read. The fueling is adjusted acordingly to cope with the sudden increase in air volume, however a faulty sensor can cause the ECU to ignore this data and the engine will "hesitate" when applying the throttle.

i read the thread with interest.do you know if it is spark or fuel that is missing when you wide open the throttle?may i suggest that you run wires to the cold start valve with a button in the car[so as to activate it] and see if the application of extra fuel changes the situation.if it does not then you can pursue the spark idea.one more thing is it poss that the flex plate where the ckp reads top dead centre is damaged or out of place?

__________________
David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
http://www.w108.org/gallery/albums/A...1159.thumb.jpg

Right, Mercedes finally put in a new Ignition control module and it solved ALL hesitation problems. Amazing really. I actually went out with them on the road test and drove the car myself. I could not replicate the problem at all. Only 30 mins before on my way to them i could replicate the problem on demand!

UPDATE:
Right guys, since MB removed my old Ignition Control Module, fitted a new one to test, removed it...Then fitted my old one back my car has been difficult to start. Before it started at the flick of a key. Now it will crank for several seconds at least before it starts...
What gives!??

had the same trouble with my 86 2.3-16. When i had the car towed to my Mbenz mechanic's shop, his diagnosis was the car had no spark. This was after I replaced all the level 2 ignition components ie car rotor plugs and coil. I swapped out the ezl module, a 30 second swap, and the car fired right up. The unit i used was from a regular 190e I believe. Car runs fine now

Is there any way to check the ICM? It is also called the EZL correct?

Its one of the only parts left that may be causing my idle misfire....I have a huge list like the OP of replaced parts.

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

As I understand the back of the EZL module is coated with a white thermal paste and uses the car's fender to act as a heatsink to disperse the heat it produces.

I read that many older EZLs fail if the thermal paste coating drys out and prevents the EZL from cooling?

Is this true?

Aren't EZLs available off eBay for like $30? I see them all the time!

__________________
2006 BMW M5 "Heidi" @ 109,000 miles
2005 MBZ C55 AMG "Lorelai" @ 165,000 miles
1991 MBZ 300E "Benzachino II" @ 165,000 miles
1990 MBZ 500SL "Shoshanna" @ 118,000 miles

(On the hunt for a good used M103 engine as of 6/10/23, PM me if you have one to sell!)