SL/R129: 1995 500SL stalling issues
Have a question hopefully someone on here can help me answer.
I am currently working on a 1995 SL500. Problems I have repaired already are, 1- replaced engine wiring harness due to all insulation powdery and non existent in other areas. 2- replace valve cover gaskets and spark plugs.
3- checked and cleaned distributor caps and rotors (slight moisture in each).
4- replaced ignition coil on left fender.
Problem still occuring;
1- starts and idles without issue when cold.
2- while idling and warming up a small mis can be heard and felt.
3- when putting under load the mis is unmistakable and car sputters and dies.
When this happens it is really difficult to start or will not start.
I got it running again and drove up a hill to see clouds coming out of the tail pipe on the driver side.
Could the issue I am looking for be the catalytic converters are clogged, and it is stalling due to really high back pressure, therefor stalling the engine?
Or is the issue the crank position sensor?
I am leaning toward the clogged cat due to the symptoms, what do you guys think?
Scott
What I see, is that the MAF is not getting enough air because the exhaust is plugged. Then the backfire I hear is not actually a back fire but a little explosion in the exhaust manifolds when a little oxygen gets in and helps ignite the fuel load between the manifolds and the cats.
Scott
Instructor of Heavy Duty and Commercial Transport Mechanics.
Vancouver Canada


