e30 not idling at all, just stalls

[jcerecke 2]

Let me paint you a picture...

So my 85' 320i has been driving fine lately but this morning on my way into town all of a sudden I slow down and stop at the intersection and the car stalls. Start it up and pull off without a problem, next intersection the same thing. Have to stop a while at this one so started it straight back up and it fired up but stalled immediately after. So I wait until the light is green, start it up and take off and basically repeat this process all the way into town.

If the car's in neutral or my foot's on the clutch then it stalls and refuses to idle.

Now this same problem happened about a year ago, and I left the car sitting around for about 4 months before bothering to fix it. I self (maybe not so correctly) diagnosed the problem to be either AFM or ICV so took both out and cleaned all the crap out of both and put it all back together replacing a cracked hose at the same time. And the car ran fine ever since.

So on my way back from town the car ends up stalling and not starting back up again. I've had it towed back to my house and while waiting for the tow, I called up eurorec to figure out what an ICV will cost me (was quoted ~$450 for a new one elsewhere) and the guy goes "nah nah nah, it won't be the ICV, it'll be the TPS switch, it fills up with oil and craps out". So at home I take the throttle body off and open up the TPS, and fair enough it looks awful. Spray the crap out of it with electrical contact cleaner and clean the inside of the TB while I'm at it and pretty much get rid of all the oil successfully. Get out the multimeter to test the TPS and both idle and WOT switches are switching correctly at the right points. So I'm a bit lost...

Do I go back to the AFM/ICV idea? Any other ideas?

[Mark 178]

I always pull out this old chestnut with threads about E30's not idling properly... is it the thermostat? If it's stuck the ECU will think the engine is permanently cold and the air/fuel mixture will be wonky, making the car run too rich causing it to stall at idle. This was the cause of my stalling problems in my old E30.

Failing that, checked your dizzy cap?

[jcerecke 2]

I always pull out this old chestnut with threads about E30's not idling properly... is it the thermostat? If it's stuck the ECU will think the engine is permanently cold and the air/fuel mixture will be wonky, making the car run too rich causing it to stall at idle. This was the cause of my stalling problems in my old E30.

Failing that, checked your dizzy cap?

AHHHH I can't believe I didn't think of that. The thermostat hasn't worked for a couple of months, wasn't sure if it was just the needle or what but I'll look into it, cheers. Yeah I've experienced lots of problems with the distributor cap too causing all sorts of weird problems.

[_ethrty-Andy_ 2122]

Failing that, checked your dizzy cap?

havent seen that old gem round these parts for a while!

[_Matt_ 42]

where is that sweet piss take vid about checking your dizzy mark?

[Mark 178]

[Lucan 196]

lol forgot about those

[Michael. 2312]

Those clips are hilarious!!

[jcerecke 2]

Got the old thermostat out and chucked it on boiling water and didn't see it move a mm. So got a new one and cleaned the housing out, chucked it in and while I was in that area of the engine I also removed the blue plug and joined the terminals on the cable to check my temp gauge, turned the ignition on but it still didn't move so I just tried to start the engine and it spluttered into life! YUSS.

Removed the bit of wire joining the blue plug's wires and it died, so plugged it back into the sensor and it all works now fine, so must've been the thermostat.

But I've still got no heat in the heater and the temp gauge still doesn't work... Fingers crossed it's not overheating!!

Edited April 16, 2012 by jcerecke

[tire 10]

Got the old thermostat out and chucked it on boiling water and didn't see it move a mm. So got a new one and cleaned the housing out, chucked it in and while I was in that area of the engine I also removed the blue plug and joined the terminals on the cable to check my temp gauge, turned the ignition on but it still didn't move so I just tried to start the engine and it spluttered into life! YUSS.

Removed the bit of wire joining the blue plug's wires and it died, so plugged it back into the sensor and it all works now fine, so must've been the thermostat.

But I've still got no heat in the heater and the temp gauge still doesn't work... Fingers crossed it's not overheating!!

Pretty sure the blue one is the ecu temp sender and has nothing to do with the gauge. Is there a brown one nearby? Thats usually the gauge one in my exp

[jcerecke 2]

Pretty sure the blue one is the ecu temp sender and has nothing to do with the gauge. Is there a brown one nearby? Thats usually the gauge one in my exp

Yeah saw the brown one too, the blue one was the only one that had two contacts. Brown only had one. But I've taken the cluster out and tightened the brass screw on the back which was loose and while it was out I've taken the SI board batteries out and just waiting for some new ones to charge overnight to see if that helps any.

[hotwire 352]

Yeah saw the brown one too, the blue one was the only one that had two contacts. Brown only had one. But I've taken the cluster out and tightened the brass screw on the back which was loose and while it was out I've taken the SI board batteries out and just waiting for some new ones to charge overnight to see if that helps any.

Blue is engine management temp, brown is gauge wire - earth it out - gauge should go high

[jcerecke 2]

Blue is engine management temp, brown is gauge wire - earth it out - gauge should go high

Yep, so after replacing batteries in the cluster and tightening the brass nut the temp gauge still doesn't move. Even after earthing that brown plug's connector. By "doesn't move" I mean when I turn the car on the needle jumps from resting position up a little bit to about halfway between resting position and the start of the bottom of the scale. Same if it's shorted to earth. Every now and then I see it jump a little bit up further into the blue when I'm turning the car off.

Pretty safe to say it's the gauge? Since it's an '85 e30 there is no C191 plug to check, I'm guessing it's just hardwired straight through to the plugs on the back of the cluster. Just out of curiosity the cluster had three sockets on the back but the middle one (yellow I think) had nothing plugged into it. Should I be worried?

Just took the car for the first spin after getting it to not stall on me, took off down the road, felt like it had more power than usual and as soon as I stepped on the brakes it stalled. Gave it another hoon and touched the brake lightly, no stall but it did stall later again just as I pulled into the driveway on my 1 minute run up the road and back down again.

Edited April 17, 2012 by jcerecke

[speedyg 16]

Shameless plug but I have these, one of them is from German auto components, fully checked etc, cost $210, I could chuck a buynow price on for you of $50. I am in Riccarton for pickup.E30 ICV

[jcerecke 2]

Shameless plug but I have these, one of them is from German auto components, fully checked etc, cost $210, I could chuck a buynow price on for you of $50. I am in Riccarton for pickup.E30 ICV

Thanks mate, but mine's the older type that connects to the cooling system.

[nath 130]

Pretty sure the blue one is the ecu temp sender and has nothing to do with the gauge. Is there a brown one nearby? Thats usually the gauge one in my exp

Can't have too many blue tops. Must keep purchasing blue tops.

[tire 10]

Can't have too many blue tops. Must keep purchasing blue tops.

I'm considering a sacrificial burning to make the E30 gods look on me favourably.

[jcerecke 2]

Ok so after replacing that blue plug and the air filter it's not stalling any longer! Hoorah.

But it was idling up weirdly. When it was cold it would idle at 1500 and then drop to between 1000-1200. It wouldn't fluctuate noticeably but maybe sitting at one set of lights it would be 1000 and then the next 1200. Even caught it up at 1500 while warm a couple times but not normally.

And if I was driving along and put my foot on the clutch it wouldn't just drop to idle speed it would sort of drop to 1500 and then slowly meander it's way down a bit further.

So I adjusted the idle screw and... now it's completely closed haha with the car idling at warm around 600. Probably not supposed to be closed though right???

[Mark 178]

Set it so it idles at 750 warm. I'd suggest someone has previously fiddled with idle screw to fix an idling issue in the past.