im almost stumped I need some help please...

[The Bimm]

Alright so my 87325 with a swapped 88m20b25 just rebuilt the head and replaced all seals and gaskets on the whole engine and tranny and its been running great but now lately its had some idle issues but a little different then normal e30 idle problems. So when i start her up she runs fine until it warms up ill be driving and as soon as I take my foot off the gas and let the clutch out the car just shuts off I have to stay on the gas to keep it running or if I slowly take my foot off the pedal until the rpms hit the idle speed and it will stay on then if I give it gas and just let my foot off normal it will some times drop to 500rpms then jump up and down then die again. I checked the continuity on the tps and it seems fine I dont know if its sticking some times I was going to clean it and I got a new temp sensor a new cps my next guess was the icv was sticking or getting stuck open or closed I dont know I was planning on getting a new one as well but I would like some input. Also before it started to just shut off it would drop to 500 rpms then go up to 1400 rpms then back to normal idle when ever I take my foot off the pedal so any input would help thanks.

[Todd Black 88]

Ouch my head hurts.

[The Bimm]

Haha same here

[dwight]

Sounds like a fuel related problem

[dnguyen1963]

Wow, I had to read your post three times to know what you are asking. Tee in a fuel pressure gauge to see what reading you get when the rpm drops. Check for vaccum leaks would be the next thing to do.

[jlevie]

As stated above check rail fuel pressure and have a smoke test run.

[Scallywagon]

Stomp test wouldn't hurt either

[The Bimm]

Yeah that was my next two things to do. I did find a crck in my brake booster hose last night. And also when I did the engine swap I had to do some wire slicing for the fuel pump to work with the new wire harness couse my e30 has the inner and outer fuel pumps and I guess the late model 325i's don't so maybe I should check those wires as well because I just replaced both those pumpsbut I will do a pressure test. And as for the stomp test I've tried it many many times and have never been able to make it work I dont know ic im doing it wrong but ic any of you have done it please explain how you got it to work.

[vpilarrt]

Your issues and the fact that the stomp test doesn't work leads me to believe that your TPS is not adjusted properly. You want it so there is continuity between pins 1 and 2 at idle and continuity between pins 2 and 3 at WOT. Is that what you got?

[E30_fiend]

I have a question for the OP. DId you swap the 88 harness in with the motor? I didnt see that listed anywhere which leads me to thibk you may have tried to use the 87 325 harness on the 88 m20. This alone could account for many of your issues including the stomp test not working.


Taylor

[E30_fiend]

Alright so my 87325 with a swapped 88m20b25 just rebuilt the head and replaced all seals and gaskets on the whole engine and tranny and its been running great but now lately its had some idle issues but a little different then normal e30 idle problems. So when i start her up she runs fine until it warms up ill be driving and as soon as I take my foot off the gas and let the clutch out the car just shuts off I have to stay on the gas to keep it running or if I slowly take my foot off the pedal until the rpms hit the idle speed and it will stay on then if I give it gas and just let my foot off normal it will some times drop to 500rpms then jump up and down then die again. I checked the continuity on the tps and it seems fine I dont know if its sticking some times I was going to clean it and I got a new temp sensor a new cps my next guess was the icv was sticking or getting stuck open or closed I dont know I was planning on getting a new one as well but I would like some input. Also before it started to just shut off it would drop to 500 rpms then go up to 1400 rpms then back to normal idle when ever I take my foot off the pedal so any input would help thanks.

I counted 4 periods in that entire write-up. In order to get better help in the future, try using a little more punctuation. Your write-up was very hard to follow when we have no idea where one sentence ends and another begins.


Taylor

[The Bimm]

Haha sorry I know I was at work so I wasnt paying attention to the writing. But yeah I used the 88 harness with the 88 engine. And as for testing the tps I got continuity with the throttle cully closed then I slowly opened it and the continuity came back around 70 or 80% to full throttle. Should the continuity still be there with the throttle all the way open and all the way closed?

[E30_fiend]

Continuity should be there between pins 1 and 2 at idle and between pins 2 and 3 at wide open throttle. Nothing in between.


Taylor

[The Bimm]

And I just had to splice 3 wires on the 88 engine harness to make it work with my 87 body harness. With the stomp test what light flashes the codes at you? Since e30s dont have CEL. Is it the check panel check light? Or the inspection light?

[The Bimm]

Alright well I got it at idle with 1and2 and then it showed up on pins 2 and 3 starting at 70% throttle all the way to full throttle. So on pins 2and 3 the continuity shouldn't show until its at complete wide open throttle? If thats the case then I should try to udjust it to that right?