Oil contamination of ECU - PeachParts Mercedes-Benz Forum

ClareB · #1 06-15-2007, 06:45 AM

My father has a CLK230 Kompressor year 2000 which is currently showing the engine management light on the dashboard. He has consulted a local garage and been told oil has infiltrated the plugs and harness/loom through capillary action from the camshaft and oil has entered the ECU. The diagnosis is to replace the ECU, harness/loom and oxygen sensor at a cost of around £1500. Has anyone experienced this problem before? Apparently it is a a common fault? Is £1500-£2000 the only option?

manny · #2 06-15-2007, 07:23 AM

I have read about this problem a few times on the German M-B forums.
Seems the only cure is to replace the parts you have mentioned.
Once the camshaft sensor develops a leak, there is a "wicking " action, that allows oil to migrate right up and into the ECU.
I would try spraying some Brake Cleaner ( it will almost instantly evaporate & carry the oil away ) into all accessible places & see what happens.

david s poole · #3 06-15-2007, 09:49 AM

if that car is an auto trans i would check the trans computer as well.they are well known for the problem which i have personally seen several times.

ClareB · #4 06-18-2007, 10:05 AM

Thanks for the info guys - very helpful. Cheers Clare

Parrot of Doom · #5 06-18-2007, 02:43 PM

Before you buy any new ECUs, clean the existing one out with alcohol. You'd have to be incredibly unlucky to damage a PCB or any components with mere oil, potentiometers are one exception but they're cheap to replace.