1987 325e running problems

[325eMattyd]

Hey guys so i have a little problem with my car...
so about 10 days ago i noticed sometimes my car would start cutting out while driving, but only for a split second at any rpm. like i'd be driving and all of a sudden the car would cut out for a split second and shake back and forth.
and it's been getting worse, now every morning i start up the car it'll do this cutting out only until its warm about about an hour of driving and i'll drive the rest of the day with maybe 1 or 2 cut outs...
what could be causing this problem?
and to save some time i made a list of parts i have replaced in the past year just because i wanted to do some preventative maintenance...
This car's engine management system is a Motronic 1.0

The whole ignition system- plugs, wires, coil, distributor and cap.
DME temp sensor.
brand VDO ICV.
throttle position sensor.
O2 sensor along with a whole new exhaust and cat.
cold start valve.
alternator.
Thermo time switch (to activate cold start valve).

i did not replace or test the Crank Position Sensor, there are in total 3 in the Motronic system of this car one is in the front of the car on top of the flywheel but it is only for diagnostic testing and not connected to the DME and it's wire goes right to the diagnostic plug, so it doesn't matter

The 2 others are in the bell housing, from what I've read one counts the teeth on the flywheel (position of the crank) and the other is a reference for the fuel injector pulses.

i was thinking maybe one of those 2 could be starting to break?
I've also checked the fuel pressure at the rail while i was driving and everything seems to be good, no sudden drops in fuel pressure.
also when i got to crank the car over for the first time it almost died but quickly shots up and starts to idle normally except for the rpms going up and down ever so slightly?

[flumph]

I had a similar problem with my '84 Eta. It turned out to be one of the contacts on the main relay that kept shaking loose. I think it was the ground contact. It sounds dumb, but check your main relay socket.

I figured out that if you whack the little box next to the airbox (with the main/FP/O2 relay in it, not the fuse box) with a plastic screwdriver handle, it killed the car. I replaced the relay and made sure the socket was seated well, and put some dielectric grease on the contacts. Problem hasn't come back since.

Probably not it, but it's worth checking it out.

[325eMattyd]

I had a similar problem with my '84 Eta. It turned out to be one of the contacts on the main relay that kept shaking loose. I think it was the ground contact. It sounds dumb, but check your main relay socket.

I figured out that if you whack the little box next to the airbox (with the main/FP/O2 relay in it, not the fuse box) with a plastic screwdriver handle, it killed the car. I replaced the relay and made sure the socket was seated well, and put some dielectric grease on the contacts. Problem hasn't come back since.

Probably not it, but it's worth checking it out.

i appreciate the advice, i replaced all the relays and put electric grease on all the contacts already except the 3 ones hanging which i believe are fuel pump, injectors, and ignition. so i just did those and tried taping them and it didn't make a difference. i hate intermittent problems.....

i did ordered a new cps sensor from the store... will update after installing the new one to see if it makes a difference.

[325eMattyd]

i also had the idea that maybe it could be the DME but i looked at it today and it says re manufactured on it so it had been replaced sometime in the car's life..

[325eMattyd]

Also im not sure of this and i can't find any information, but do the 2 cps sensors in my bell housing both have the same part number? or are they both different sensors?

[325eMattyd]

night bump