R129 misfire

[jondoel]

Problem:- Once warmed up (about 15 – 20 mins) car starts to cough and splutter, shudder, misfire, backfire lose power and the engine dies. Then it won’t start (only backfires if you try) until 30 – 40 minutes have passed, then it’s perfect for the rest of the day. Really embarrassing at lights etc. Most diagnoses have been the Crank Position Sensor which I have had replaced twice.

Solution:- I took off the distributor caps and found they had moisture and dirt in them and some deep arc tracks around the the place. Cleaned and polished them and hey presto all sorted.

Now for the ASR problem...

 

[neilrr]

Year? Engine?

Those kind of details would be handy to know.

 

[jondoel]

quite right - 500, 1994

 

[Sp!ke]

What are the symptoms of the ASR problem?

 

[EDZ649]

Be interested to know what the ASR problem is too as I have an issue with mine, been diagnosed to a fault within the ABS pump...

 

[GregE240]

Common problem on the M119 engine. Later distributor caps have better seals (I am told) and so reduce this particular issue.

Also, if you ever need to replace them, get the BOSCH part rather than going to the stealer for the MB part - they are one and the same save an MB badge and an MB part number stamped on one and not the other.

It was one of the first jobs I had to do on my SL. Has run sweet as a nut ever since.