Yesterday while I was driving to work at ~80mph, my 190e suddenly lost power. I drifted to the right lane, and was just at my exit. The engine idles smoothly, and has diminished but still moderate and smooth power through ~2500 RPM. Above that it sputters, and will produce no power. I checked the obvious items, to no avail. I checked the airflow sensor transmitter with an ohmeter, and it has a smooth resistance curve. The throttle valve switch has no continuity that I can discern, nor a resistance curve as a throttle position sensor should. I have appropriate fuel pressure, though I have been unable as of yet to monitor that with the engine running at various loads. I'm inclined to believe that fuel starvation may play into this situation, but am perplexed as to how that would have suddenly occurred since there has never been any inclination to suspect any problems prior to this. Under load, the engine will ping loudly if the throttle plate is opened more that what the engine is capable of running at. Please advise if I am missing anything obvious, or if you have any suggestions, PLEASE advise.

Mine did that once. My cat was clogged from some debri I did not get out when I gutted the pre-cats. Luckily I could get it out by cutting the cat off and clearing the pipe then re-attaching the cat. I found it though by disconnecting the exhaust at the down pipes and the exhaust manifold and rev'ing the engine and it actually went to redline. Before even in nuetral it would not rev past 3500RPM. This clogged when I was on a highway and the engine could not go past 2500RPM and hold speed. This sucked big time.


Edit: Also you do not have to take the bolts all the way out, there are only 4, you just need to loosen them enough to make the exhaust leak. Lose but not all the way out. Enough so you can seperate the exhaust to relieve pressure. Then if you can rev and run right you have found your problem. Do you use fuel injector cleaner ever? The cat's get clogged normally with that kind of mileage and a piece of carbon or pieces could have blasted out of the cylinders over time and caused it. If it is that. With those miles though I am betting on Cat.

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~Jamie
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2003 Pewter C230K SC C1, C4, C5, C7, heated seats, CD Changer, and 6 Speed. ContiExtremes on the C7's.

1986 190E 2.3 Black, Auto, Mods to come soon.....

The cats were replaced at 225K, but thank you for your reply, I will of course check them. I'll see, it could be the pre cats.

Must be the pre cats. I quickly checked by loosening the exhaust manifold, and voila! Only ran it for 10 seconds, just to check (didn't want to burn any valves). I'll be pulling the exhaust apart tonight. Thanks for the heads up, that problem escaped me.