My girlfriends 88 Sedan Devile acts crazy ... its about 95K but it's acting like that since she got it ... 15K or so. It looks like it's getting worse at the time. You start it up ... and it actually acts like it's trying do die ... right then the idle solenoid kicks in .. and revs up to verry high RPMs ... and again in loops ... gets low and idle solenoid kicks in:want: ... jumps are severe beetwen 700 - 2000 rpms ... the bad thing is also it does the same while driving ... revs itself up ... accelerates ... once she even smashed a guy when unparking it jumped on the reverse ...

Any suggestions? .. maybe someone had the same problem or it's a common issue ... any help greatly welcome ..

Mike

Read the fault codes. I'd be willing to bet you have a bad MAP or TPS sensor. Could also be a vaccume leak.

When you step on the gas in park, does it seem to rev up steady, or does it sound like three or 4 quick jumps in rpm? If it's the latter, you are probably getting water in your cylenders. Check the coolant level. A bad head gasket will cause an engine to rev like that.

Also, try holding your hand in front of the tail pipe. If you have a bad head gasket, you will feel the water in the exhaust. You can't always see the white smoke.

I would suspect the idle speed control motor is starting to get sticky/failing..... The closed throttle switch inside the idle speed control motor has to work correctly for the idle speed control to work. Sounds like the closed throttle switch is not closing when the throttle is released and the idle speed control system is not working...then it suddenly trys to prevent a stall when it sees the RPM dip too low.


The idle speed control motor is that little can on the throttle body with a plunger sticking out one end that the throttle lever rests on. Lots in the archives if you search using "idle speed control motor" or "ISC motor" or "closed throttle switch"