Scratching me head...new BMW owner.

[Jdbush2010]

So I just recently bought my 1986 325es. I've been searching and searching and trying stuff but to no avail. Specs on the car:
1988 super Eta 2.7it bottom end
1988 2.5it head
Full motronic 1.3 harness
Intake swap
272 cam
E36 Bosch blue top injectors
Tuned ECU by MarkD
Ireland engineering long tube headers with MagnaFlow muffler

Here's the problem I'm having. It runs super rich after a few minutes and hardly wants to idle. Sometimes it's great for a little while longer depending on how hard I beat on it. When driving at minimal throttle cruising it will start to buck and miss and sputter but when I give it more skinny pedal it clears out and takes off like crazy. I don't like running it that hard must to be able to drive. It's my daily so I have no other options but to drive it.
If it acts up and I beat on it it will clear up and be fine for a short while then start again.
I have checked for vacuum leaks, no smoke test. Just the carb and coke cleaner method.
Changed both coolant sensors (gauge want working properly)
Changed maf with known working unit as well as tps, icv, icm, and fpr.
Put new plus in, and it helped some
Checked the o2 sensor and it was dirty, I was assuming it was due to running rich. The hard wires were also twisted and black taped... So I stripped them back to the good, non corroded parts and soldered and heat shrank them.
I did check the c191 and went ahead and did the fix for that for good measure.
Now I have gotten the car to run great with no problems for a couple days last week... Then it returned just as I was telling my buddy how glad I was that it was fixed. Just my luck.
So here I am not knowing what it is or how to start.
I have only tested one thing and that was the cts. Coolant sensor tested good. Had the correct resistance. Now when I checked the ecu it wasn't cooperating. Cts read I think 330 ohms whereas ecu was reading somewhere like 1400 ohms if I remember right.
Any input is nice. Sorry if it's in the wrong section, this is my first post and I'd really like to enjoy my car. I was pro gm before but love my e30. Thanks! I hope that's enough info

[Ether-D]

Crank sensor would be a good one to check. The wire gets chewed by the crank pulley and it can ground out erratically causing your symptoms.

[Jdbush2010]

That was going to be my next thing to check. I'll honestly be super upset if it is cause I looked at that thing and thought about it and never checked. I'll consult my Bentley manual and test it accordingly

[Ether-D]

The continuity test can be a false negative. If the wire is not warm enough to be touching the pulley it will test good when it's bad. I think they are about $40 on eBay.

[Kershaw]

I'd also swap your tuned DME with a stock one and see how that changes things.

[Jdbush2010]

I'd also swap your tuned DME with a stock one and see how that changes things.

I swapped the dme and the ecu with stock units with no change. If I keep throttling at cruising speeds there isn't a problem. I could do this but some of the law enforcement around here may frown upon that

[StereoInstaller1]

So I just recently bought my 1986 325es. I've been searching and searching and trying stuff but to no avail. Specs on the car:
1988 super Eta 2.7it bottom end
1988 2.5it head
Full motronic 1.3 harness
Intake swap
272 cam
E36 Bosch blue top injectors
Tuned ECU by MarkD
Ireland engineering long tube headers with MagnaFlow muffler

Here's the problem I'm having. It runs super rich after a few minutes and hardly wants to idle. Sometimes it's great for a little while longer depending on how hard I beat on it. When driving at minimal throttle cruising it will start to buck and miss and sputter but when I give it more skinny pedal it clears out and takes off like crazy. I don't like running it that hard must to be able to drive. It's my daily so I have no other options but to drive it.
If it acts up and I beat on it it will clear up and be fine for a short while then start again.
I have checked for vacuum leaks, no smoke test. Just the carb and coke cleaner method.
Changed both coolant sensors (gauge want working properly)
Changed maf with known working unit as well as tps, icv, icm, and fpr.
Put new plus in, and it helped some
Checked the o2 sensor and it was dirty, I was assuming it was due to running rich. The hard wires were also twisted and black taped... So I stripped them back to the good, non corroded parts and soldered and heat shrank them.
I did check the c191 and went ahead and did the fix for that for good measure.
Now I have gotten the car to run great with no problems for a couple days last week... Then it returned just as I was telling my buddy how glad I was that it was fixed. Just my luck.
So here I am not knowing what it is or how to start.
I have only tested one thing and that was the cts. Coolant sensor tested good. Had the correct resistance. Now when I checked the ecu it wasn't cooperating. Cts read I think 330 ohms whereas ecu was reading somewhere like 1400 ohms if I remember right.
Any input is nice. Sorry if it's in the wrong section, this is my first post and I'd really like to enjoy my car. I was pro gm before but love my e30. Thanks! I hope that's enough info

Hey man, welcome to R3V. I too was a GM tech for a while, but the E30 was just too big a draw.

Got a fuel pressure tester? Im guessing some sore of fuel pressure issue...leaky injector, leaky FPR, bad vacuum line, something along those lines, In a GM one might assume TPS for the issue you are having, the E30 TPS is just a WOT sensor, doesn't care about nothing, it's just a toggle switch.

Best of luck, and welcome to R3V!
Luke

[Jdbush2010]

Hey man, welcome to R3V. I too was a GM tech for a while, but the E30 was just too big a draw.

Got a fuel pressure tester? Im guessing some sore of fuel pressure issue...leaky injector, leaky FPR, bad vacuum line, something along those lines, In a GM one might assume TPS for the issue you are having, the E30 TPS is just a WOT sensor, doesn't care about nothing, it's just a toggle switch.

Best of luck, and welcome to R3V!
Luke

Thanks man! I pulled the injectors out a couple days ago and none leaked. I haven't had the chance to flow them or anything. It hold good pressure and doesn't leak off. Cold starting isn't an issue either. Within a couple cranks it's up and running. It doesn't have a cold start injector. I have a video to upload and hopefully you guys can learn from it. Makes it a bear to drive in town and it's ruined the fresh oil change...

[Jdbush2010]

https://youtu.be/aaho_TA1cdI

There is the link. I'm not sure how to upload lol

[Jdbush2010]

So took the crankshaft sensor off to inspect it and found the wire had been rubbed down to the core. The yellow wire to be exact. My problem was I ordered one yesterday and it wasn't to be expected until Friday. So got ahold of my guy who is parting out a couple e30's and he had just the one I needed. Granted it was an hour drive one way but the cps was brand new! Didn't have a spot of oil on it and scored it for 20 dollars.
So I installed it. Ran great then slowly got worse. Couldn't figure it out. Drove it rather hard when I was headed home because I was kinda pissed at it. Turns out she looked it. Cruising speed it was grand, never acted up once. Idled at the stop lights and all perfectly. Granted it was 1100 rpm but still better than erratic and around 500. So I'm crossing my fingers that it is all fixed. I'll keep updates

[StereoInstaller1]

Awesome. The Motronic 1.3 setup is super simple, easier than TBI even!

[Jdbush2010]

Well may have spoken a little too soon. It started doing its thing again unfortunately. Last night it ran great. I'm so confused. I've never had a car be this much of a pain before

[Ether-D]

I'd wait til the new CPS gets there and then form an opinion. The used one could still be bad. Don't give up on the car. You're almost there.

[Ether-D]

It also sounds like your icv is sticking. Remove it and wash it out.

[Jdbush2010]

I'd wait til the new CPS gets there and then form an opinion. The used one could still be bad. Don't give up on the car. You're almost there.

I haven't fully given up but my hair seems to be getting thinner at an accelerated rate. The cps did help a ton. Also may switch back to the other afm. It's a new unit supposedly and it's a free swap. I checked the icv last night and it was filthy. I have two of them. One I got recently and one that came on the car. I put the cleaned new one on. I don't know if it matters but I unplugged the tps and it did nothing for idle or wot. I need to invest in my own multi meter soon