E30 Occasionally Kicks/Jerks While Driving .. similar feeling to Fail Safe Mode??

[olegd88]

Hey guys,

I have a M20 E30 5 Speed.

Today I had several times where the car "jerked/kicked" while driving. This happen for a split second, clutch was NOT depressed, in gear and accelerating. (slow or quick acceleration does not seem to make a difference).

The feeling is as is for a split second you slammed your brakes, or quick depressed the clutch. It happens quickly enough for you to not have time to really do anything until it goes away.

Happened in 1st gear .. at about 3-4k rpm - saw rpm needle jump +- 600 rpms.... but only happened once in 1st - this was in traffic. Also happened in 2nd, 3rd and 4th - at completely random times.

Tried hard accelerations, slow accelerations, higher rpms, lower rpms - it would happen but with no pattern and totally at random times.

Engine seems to be running perfectly with great idle and revving.

What could this be? I "feel" like it is a drivetrain issue.. clutch?

Any ides / advice?

[DesertBMW]

coil wire or distributor rotor, bad crank sensor...

[olegd88]

Thanks! Is there a good way to diagnose it? The engine revs fine, idles fine and there is no check engine light.

[zig553]

Last time this happened to me I had water on the CPS. Try drying the CPS off and see if it fixes it.

[rcsoundn1]

This to happens to me from time to time. My car also has a very slight miss-fire though. Never tried to fix it yet.

[olegd88]

Thanks guys, I will check the sensor over the weekend!

[mikelat]

Check the grounds too, make sure they are nice and clean.