Thalweg

I recently purchased a 1995 SL500. Great condition. One owner, 72k miles. The soft top has never been put up, the windscreen has never been installed. However there is a problem.

The car turns over fine, idles smooth. Runs fine, feels powerful, fine until it heats up. Drive it a few miles and give it any gas and the car feels like like it has lost its power past 2-3k RPM. Then the engine cuts out.

I have heard plenty of possible fixes. The dealer (not a MB dealer) wants me to replace the ignition coil. I have also heard fuel pump relay, battery, caps and rotors, wiring harness, crank position sensor. Anyone know whats going on?

SLCL

Does it cut when you are stationary? Can you start it right away? You might want to describe a little more in details.

Thalweg

It doesn't cut out sitting still as far as I know. Had it running for a half an hour, although that was at night so the ambient temperature was cooler; any heat related issues might not have come up. It starts up right away on a cold start, idles very well, its just under acceleration after a few miles of driving that it displays any symptoms.

Thalweg

Well, I drove it tonight to see if I could further deduce what the problem was - fresh tank of 92 octane, hopped on the highway - car was running fine. I have half a mind to think the stingy used car dealer had filled it with the wrong grade of fuel. Regardless, I'll be taking it to my local MB dealership to get it inspected and get a 75,000mi tune up.

SLCL

Where are you located? Did you see any error code? I had the CPS issue a while ago and it would not start while engine hot (no codes). You are saying that you were cruising and it shut off? The more [in details] you describe, the more likely you'd get help. It could be just a simple problem and by the time you get out of the dealer, you only have one arm and one leg left. Hope it was just the fuel grade as you'd thought. Good luck.

prathermj

Really hard to tell without driving it. But, the usual suspects on a '95 are the main engine wiring harness, starter/pos wiring harness, caps and rotors. Caps and rotors have a strong tendency to crack, which will often be made worse by heat. Caps and rotors are easy to replace with even modest mechanical skills. Wiring harnesses degrade to an alarming degree in a '95 and cause a multitude of confusing problems. I would pull the codes on the 38 pin (likely you will get no codes) and run some approved fuel injector/fuel system cleaner through a tank and see what happens.