My fathers W129 500SL recently had some ASR issues. I am somewhat handy and replaced the Electronic Gas Actuator at the front of the engine, this took care of the ASR light on the dash but it still doesn't run as good as I feel it should, still feels like we are having an ASR issue. My question is the last time my father drove the car when he came back it was running pretty bad, but I noticed that the car seemed very hot, I looked under the car and the cat. converter was cherry red, had to be very close to catching fire. Is there a specific part that this clues anyone to what my problem may be on the particular car? My conclusion is some part has failed and is dumping way to much fuel into the system? Thanks

If fuel is not burned completely in the combustion process, raw fuel can cause the catalytic converter to get RED hot. And that will ruin the converter.

Miss fires are the most common issues: spark plugs, dist caps, rotors, & SP wires are the most common causes.

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I'd be worried the converter melted down and is now plugged. That will cause a big loss of power.

-J

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Thanks for the advise, I will check the plugs and wires, I replaced the distributor caps and rotors not long ago. I may also try dropping the exhaust and seeing if that helps the problem since the converters could now be bad.

don't drop the exhaust, just pull the o2 sensors. might be easier. good luck, chuck.