M20 2.7i won't idle but will rev

[dumpski88]

I have a 88 e30 with a seta bottom and an I head I just put in a 89 325i ecu 0261200173 I also have put on a new exhaust and I haven't put the o2 sensor on because there wasn't a spot on the headers. But my problem is that I can start the car and it will just die and won't idle but if I give it gas while starting it and make sure the engine won't die it revs fine and drives as long as it don't let the car try and idle but I did notice that at low revs it has a lag. I was thinking that it could be o2 sensor and fpr if anyone has any advice it was be much appreciated... I've looked on the internet to see if anyone else has had the problems but I haven't really found anything besides the opposite

[Swanny]

No idle ever? Vacuum leak? Check all your hoses and clamps.

[dumpski88]

I have no vacuum leaks I just put the ecu in today before I was running motronic 1.1 and it was on the high side for an idle but it didn't fluctuate in idle so no dips on idle

[dumpski88]

And yeah no idle ever it just dies

[jlevie]

If using the AFM from the SETA engine, swap it for one for an M20B25.

[dumpski88]

Yeah I was thinking that could be it so I going to try that tomorrow and see if that will help the idle

[Hobbit]

Hi everyone!
I see you have not posted for a while. If you read, have you managed to solve your idle problem?
My M20B20 Motronic 1.3 conversion setup from L-Jetronic has the same problem. It doesn't idle at all, and dies suddenly if I didn't hit the pedal. I've changed the AFM, so I am currently using the Motronic stuff, I have checked the IAC, it has the correct resistances between the poles, TPS works as well. Vacuum leaks causes higher idle rpm, but I have 500rpm at highest, but it mostly is between 0 and 500 :S
Any idea from anybody?
Thanks for the help...

[squidmaster]

Try adjusting ICV. Sounds like AFM, vacuum leaks, or ICV to me.

I've had a few people that had rough idles get tuned and the idle problem pretty much disappeared. But try that as a last resort.

[Hobbit]

Try adjusting ICV. Sounds like AFM, vacuum leaks, or ICV to me.

I've had a few people that had rough idles get tuned and the idle problem pretty much disappeared. But try that as a last resort.

Thank you for your reply.
Surely I do not have vacuum leaks. All the hoses has been replaced to silicones, and welded aluminium pipe. My AFM has worked fine in my friend's vehicle. Maybe the ICV settings are wrong.
Bad O2 Sensor or bad temperature sensor can causes idle problems like I have?

[dumpski88]

In the next hour I'll be getting a 325i afm and I'll let you know if that solves the problem.

[dumpski88]

So I just got a 325i afm and it still won't idle and just dies

[dumpski88]

So I cleaned the icv and it still won't idle still just dies

[Hobbit]

Have you replaced your temperature sender in the thermostat housing? The blue one...
I have changed yesterday, It was broken but by an accident my belt torn, and I have broken two rocker arms in the head too. I try to repair the damage I cause asap and I will let you know that change helped the idle problem or not