Author Topic: 1991 E30/318i Stalling (Read 4688 times)

brad59lay · « **on:** April 21, 2019, 09:25:32 AM »

Looking for advice. My 91 E30 M42 will stall out occasionally when warm. I get an engine light and it slowly loses power at both highway speeds and slower speed. When it eventually dies I can turn the ignition off and then it starts up and runs normal for a period of time until it repeats. Runs great between episodes. I get a 1241 on the stomp test. I�ve replaced the mass air flow (MAF) with both a rebuilt and an aftermarket. Also replaced all four ignition coils. Fuel pump and filter replaced last year and only a 1000 miles on them. Anyone have a similar issue or have any ideas before I take it to a shop?

DesktopDave · « **Reply #1 on:** April 21, 2019, 06:04:19 PM »

Welcome to the club!

Sorry to hear about your troubles. I'd be very tempted to check the crank angle sensor, along with the cam sensor and perhaps the DME temperature sensor. Crank sensor should show about 700 ohms between pins 1&2 when cold. It's possible the sensor is flaking out when it gets warm, or has a lot of crud on the sensing end, or is slightly too far from the tone ring on the crank damper wheel.

brad59lay · « **Reply #2 on:** April 21, 2019, 06:39:24 PM »

Thanks. I�ll try your suggestions. I was unaware of those parts even though I�ve owned the car for 20 years and other than head gasket replacement I've been lucky and done most of the repairs myself. I'll probably just replace the parts you suggest one at a time and hope it fixes the issue. Btw I noticed the 318i in your photo is the same red as mine. Mine is a 4 door and I couldn't tell from the photo if your was also a 4 door.

bmwman91 · « **Reply #3 on:** April 21, 2019, 11:26:34 PM »

See here for an idea of what to look for if you go digging around with the crank sensor and damper wheel. I suspect that many of these cars are suffering from failing damper wheels. It is an easy to replace but expensive part which I suspect may go NLA in the near future. I JUST replaced it (had to be ordered from BMW Germany) as well as the cam & crank sensors, among other things. It's like a whole new car now! But, in my case the failed part was very obvious.
http://www.m42club.com/forum/index.php?topic=19664.0

Since I JUST went through this, here's a snap from the factory ETK manual regarding resistances of sensors:

My crank sensor measured 518 Ohms cold (~20C) and 590 Ohms on a hot engine. This makes perfect sense since the temperature coefficient for resistance of copper is ~0.393% per degree Celsius. That 72 Ohm increase would correspond to a ~35C temperature increase, or a sensor at ~55C, which seems reasonable. So you can expect the resistance value you measure on this, and other resistive sensors with copper coils, to vary with temperature.

Your issue also sounds like it could be a dying ignition coil.

brad59lay · « **Reply #4 on:** April 22, 2019, 08:04:36 AM »

Thanks for the advice.
I assume the camper wheel is this part:

http://www.realoem.com/bmw/enUS/showparts?id=AJ93-USA-09-1990-E30-BMW-318i&diagId=11_4319

What should I look for to check for failure in the damper wheel? Do I need to remove it to check? Also I will likely replace the crank sensor as it is original and completely covered with oil and grease. Do you recommend the more expensive BMW part of the lesser Bosch?

I recently replaced all four ignition coils.

I've owned this car since 1999 and I am the second owner. It was in outdoor storage for 8 years while i was overseas. I brought it back to everyday driver status a couple years ago with many replaced suspension parts, cooling system, head gasket, etc... It has 150k miles and runs/drives great

Appreciate any advice to get back to everyday driver.

bmwman91 · « **Reply #5 on:** April 22, 2019, 12:28:44 PM »

The damper is very easy to remove, all you need to do is take off the belts and remove the 6 13mm bolts holding it to the crank hub. It may take a little gentle prodding to pop off. Check out the photos in the thread I linked in my earlier post; it gives an idea of what to look for.

The sensor being oily and dirty is not necessarily an issue. Clean it off and inspect for damage to the cable sheath, and verify that the resistance is in spec. Some people have said that the car will not run on the cheaper Bosch part. However, I bought the more expensive "genuine" sensor, and the actual sensor head looks like the exact same Bosch item as the cheaper ones, but possibly with a more OEM-looking connector. So I am not sure what to recommend here since it might be a waste of the extra $140 to get the "genuine" one.

DesktopDave · « **Reply #6 on:** April 24, 2019, 08:16:13 PM »

I'd usually recommend testing stuff out too, just replacing defunct parts. If it doesn't need to be done, I usually tend to wait on it.

I see that you've replaced all the coils. Did you do that for general maintenance or to track down a problem? I'm only wondering because these Bosch ECUs tend to flake out due to broken solder joints on the coil driver transistors. I've even seen a few with fried transistors. If that's the case, new coils are a temporary solution. The cold solder joint and/or damaged transistors can even take out a new coil.

Mine's a brilliant red 318i sedan too. The one-year bargain basement special! I try to be fair though, I've also (briefly) owned a 318iS coupe and I've passed up probably five 318Ti than I can recall. They're all nice cars.

brad59lay · « **Reply #7 on:** April 24, 2019, 08:23:54 PM »

I replaced the coils as a possible solution to this stalling. Also general maintenance as they were quite old and possibly original.
I just drove the car and it lost power just 5 minutes after starting. When I accelerated it lost power and then continued to lose power until I stopped the car. It was barely idleing. I turned the ignition off and immediately started the car again and it ran normal. Then after the ignition was off for about 30 mins I started the car and it started very rough. I started again and it was normal. It ran normal for the 15 min drive with one minor episode of sluggish acceleration. I'm deciding which parts/repairs to do first.

DesktopDave · « **Reply #8 on:** April 24, 2019, 08:42:00 PM »

Definitely check that crank sensor and the crank wheel. I was just catching up with BMWMan91's crank damper failure thread. It's a relatively rare occurrence but I've heard about it more than once.

The 1241 error indicates the AFM has a problem. Potentially the idle air valve could also be at fault. Have you ever replaced (or deleted

) the rat's nest of vac & coolant lines under the intake manifold? Any air leaks there will cause running problems.

I'd guess the rebuilt unit is OK, is the harness connector damaged or wet? I'd test the AFM out too. Next time the car misbehaves, disconnect the AFM and see if the car's idle improves. It won't be able to rev, of course, but if the AFM had problems the car's idle should change once the harness is unplugged.

I'm just brainstorming, but you've already eliminated all the other common E30 culprits, right? Ignition switch is OK? Fuses are good, not too loose in the fuse box terminals? No melting fuse box? Start wire is securely connected everywhere? You've disabled any original anti-theft systems?

I don't think the M42 cars have a DME code box. IIRC they didn't, but it's a common problem on other classic Bimmers.

Author Topic: 1991 E30/318i Stalling (Read 4688 times)

brad59lay

1991 E30/318i Stalling

DesktopDave

Re: 1991 E30/318i Stalling

brad59lay

Re: 1991 E30/318i Stalling

bmwman91

Re: 1991 E30/318i Stalling

brad59lay

Re: 1991 E30/318i Stalling

bmwman91

Re: 1991 E30/318i Stalling

DesktopDave

Re: 1991 E30/318i Stalling

brad59lay

Re: 1991 E30/318i Stalling

DesktopDave

Re: 1991 E30/318i Stalling