My 1990 245 was running GREAT for several weeks after replacing the intake manifold gasket and fixing a vacumn leak. Then the other day, I was driving it to the car wash. It started missing a bit. This also happened a week or two prior, but went away after a few minutes.

I didn't think much of the miss, and pulled into the car wash. Santa got me some free car wash tickets, but it was to one of those drive through places (I prefer to wash it myself, really). Anyhow, by the time I got out, the car would barely run. Very much loss of power, I could hardly accelerate. I wonder if the car wash had anything to do with it??? It did start to miss before going in. I left the engine running as instructed and put it in 'N' while being pulled through the machine.

I thought I was maybe in limp home mode somehow. I was able to drive it home, only about 1 mile, so I did. Sure hope the timing belt didn't jump! Shouldn't have gotten wet though, even in the car wash, spash guard is in place, etc... 230 is interference engine. Cranks fine though, with coil wire off, nice and smooth crank, so I think engine is OK. Need, i think, to check AMM. It is original. From description of this thing, I don't see how they last more than a year or so at those temps. Hot air pre heat hose is off air box, so if AMM was out I don't think it was a faulty air box thermostadt.

I let it dry out a couple of days, no luck. Will start, but it very rough, violent shaking, etc... I sprayed wd-40 inside dist cap. Car has had weird pattern in cap since it was rebuilt a year ago. Horizontal lines burned inside the cap, arching always counterclockwise back to the side of the terminals, not buring ON the terminals, but arching to SIDE of terminals. But that was going on even when it ran GREAT.

I'l really stumped. I thought it was probably water in dist cap, until I cleaned it out really good. I guess it might be the AMM. I don't think it was the car wash. Air filter was dry, I wonder if it somehow could have gotten water in the FUEL??? Could plugged Cat. Converter cause this?

I also cleaned the plug wires. I'll get a cap and rotor, but doubt it'll fix it.

Diagnostic socket reads 2-1-4 (RPM sensor) but functional test (press 2x for 1 sec) shows throttle position sensor and RMP sensor to be OK. (return codes 3-3-4 and 1-4-1, respectively) I replxed the speed (RPM) sensor in 1997 based almost only on the diagnostic code and it fixed the car, but that time I didn't know how to do functional test and then it would not start at all. Could RMP sensor really be at fault (like computer indicates) even though when asked to test it, is tests OK. Or does this just test that it's being actuated, etc... (not necessarily functioning properly).

Can't drive the car at all at this point. I hope I didn't damage it by driving it home, it was coughing and shaking quite a bit (guess that WASN'T 'limp home mode'? It was new years eve, didn't want to leave it out or try to call a tow.

Could something have been knocked off underneath (need to check 02 sensor wire, I guess).

Thanks for reading. Any ideas?