$500 in parts- now have stumbling issue

[bimmerboy12]

Decided to do some preventitive maintenance on my perfectly running 88 325i cabby, so did the following:

Oil pan gasket (shortcut method used)
valve cover gasket
camshaft seal and o-ring
timing belt
reference sensor
coolant temp sensor
wires
cap
rotor
belts
hoses
water pump
plugs
coolant flush

I got everything at Bavarian. I double checked all my electrical connections and cleaned with contact cleaner.

SO, when it started, it ran pretty good cold, but once it started warming up, started stumbling at idle. I can rev it up and it sounds good.

Don't suspect ICV since it ran fine before.
Check engine light was on right after finishing installing the parts, but disconnected battery and reconnected and it was not on after that.

What the flying f***.

Any help would be appreciated- you guys have bailed me out in the past so don't let me down now!
(thats you stereoinstaller)

[Aptyp]

lol, hate when that happens. don't fix what's not broken?

adjust your throttle and afm. masure all spark plugs fire. go over everything you did.

[bimmerboy12]

lol, hate when that happens. don't fix what's not broken?

adjust your throttle and afm. masure all spark plugs fire. go over everything you did.

Would my throttle/afm need adjusting as a result of what I did? I dont see how anything I replaced would affect these components....

[StereoInstaller1]

Any help would be appreciated- you guys have bailed me out in the past so don't let me down now!
(thats you stereoinstaller)

what the hell, when did I become some kind of tech guru outside of electrical shit?

Srsly, if it runs OK cold, but stumbles when warm, I would check the O2 sensor first, then clean the ICV, maybe test the coolant temp sensor.

GL!
Luke

[bimmerboy12]

OK, tested the O2 sensor and coolant temp sensor, and they both tested fine. cleaned my ICV. Still does it, and to add a twist, seems to idle better when i disconnect the harness from the coolant temp sensor... and its more of a wavering idle rather than a stumbling idle. Revs up and drives great. Throttle response SUCKS. If you give it a quick tap, it almost stalls. What is going on???

[bolognablake]

Are you 100% sure you've got your plug wires in the right order?

[bimmerboy12]

Are you 100% sure you've got your plug wires in the right order?

100%. They have the numbers printed right on the wire and cap. I just drove the car to go to the Y, and it was opposite of the problem: the car idled like shit right after it started cold, then got better as it warmed up. Remember, the car ran and idled great before all this work was done...

[xLibelle]

upon first read of the list you have there, it sounds to me like its the coolant sensor. Swap them back and see what happens.

[Funkmasta]

coolant temp sensor for sure

[Funkmasta]

put your old one back in...

[bimmerboy12]

put your old one back in...

Swapped my old one back in... made no difference. It idles OK when cold, but after warmed up, definitely stumbles. The stumbling is not even detected by the tach, it just vibrates the shit out of the car, like a random miss. This is getting REALLY F***ing annoying. I tested the CTS and it is good. Remember, it idled fine before beginning this job.

[Funkmasta]

did you swap the temp sensor that goes to the ECU or just to the cluster? It is the blue one that goes to the ECU

[abepark]

double check your spark plugs and wires, check that the wires are on tight and all the plugs are tightened to spec. is there any unusually noise near the distributor? sounds like a misfire so check all spark.

[bimmerboy12]

did you swap the temp sensor that goes to the ECU or just to the cluster? It is the blue one that goes to the ECU

Yeah swapped the correct one. Never touched the sending unit plug.


I will double check my wires. This doesn't sound like a coil does it?

[bimmerboy12]

well update for everyone, the problem is not fixed. I verified all connections are good. I am at a complete loss. Any other ideas of what to try???