Weird cruise control

[bowtie2bimmer]

My cruise works fine off and on. But when i try to accelerate using the lever it nails the gas for a few seconds, then lets off, and repeats. Its very abrupt. I assume something is wrong. What could it be?

[vpilarrt]

I would start with the parts under the hood. Could be the CC motor assembly or the Bowden cable is sticking.

[bowtie2bimmer]

how can i check these?

[Skoobeesnak]

I am having a similar issue it is very hit or miss whether or not it works. At times I can go 20-30 miles at a time then all at once it will just turn off and start jerking around. Are you able to use it once it is set? I am thinking it could be a bad vacuum hose somewhere but will be watching this thread and I will follow up if I find anything else.

Mike

[vpilarrt]

^^^ The E30 cruise doesn't use vacuum like other makes, its all electric.

Looking at the schematic it looks like the black and the blue wires at the cruise module under the hood are the leads for the electric motor. Its probably something like hot on blue and gnd on black makes it pull and switch ploarity to push (or visa-versa). There's a solenoid on the green wire which might have to be powered for the motor to run.