M50 engine trouble.

[lukasbmw]

Yesterday I go to take a left hand turn at about 30mph or so. After the turn I try to accelerate, nothing, the car bogs and will not rev. I floor it and nothing happens. The car stumbles around idle and almost dies. WTF? I turn it off. Pop the hood. Everything looks alright. No smells or leaks. How is the oil? Slightly low but still in the safe area. I add a bit just to make sure that is not the problem. Start it up...runs like a champ.

Later that night on the way back from the gym, the car is running great. I go to make that same exact turn and the same thing happens. The car bogs. I shut it down and start it right back up again. The car runs fine again but now I am concerned.

What about this turn is making the car bog and not run?

At first I thought oil pickup problems. But the oil light would come on and I would probably hear some terrible noises.

A friend suggested a bad ground, but the grounds look OK to me.

I start her up this morning and she runs well all the way to ASU. However, just now, coming home, she bogged twice and I had to restart her twice. As I pulled into the driveway she bogged and shut down again. Now I'm afraid to restart the car.

Any idea what the problem may be? I'm totally confused. I don't think it is oil, nor a bad ground. I was thinking bad gas, but I've already used half a tank and this problem just started yesterday.

[lukasbmw]

I should mention fuel pump and fuel filter are 8 months old. I bought both brand new from BMW and installed them last spring.

[SchnellerVert]

MAS the elment sounds like it's dirty, disconnect it and see what happens besides erratic idle.

[Addissimo]

I had a very similar problem, I replaced the ecu, wiring harness, afm etc to no avail. I said fuck it, and went with sds. Well, while I was wiring my sds system, I came to notice that I was not getting a switched 12 volt signal at the c101, I josteled the wires around, which didnt help. I went under the steering column and played with wires there, and I got a 12v reading. It's too cold outside to fuck with the wires, so I haven't been able to completely trace the problem down, but I'd say its a wiring problem of some sort, next time it happens, take your c101 wiring diagram out to your car with a voltage meter, and see if you're getting power to your switched 12v signal. I think its pin 6, but check to be sure.

-addis

[SchnellerVert]

His car has been built for quite some time I doubt it's wiring issues. It could be an Idle stabilizer valve aka ICV, the under manifold vacuum lines get brittle with age and crack devoloping a leak in system.

But for ease i would check the first item I mentioned. On a quick note you still have a K&N did you recently oil it. The MAS could have oil on it. It fouls the siginal and it goes to limp mode.

[vlad]

I also think it is electrical. I had the same problem everytime I would hit a bump on a road, turned out to be loose ECU connectors

[blunttech]

ill third the wiring issue. the fact its been together a while even more reason to suspect a loose or bad connection. an oily maf wont be intermittent. somethings corroded, loose or shorting when you turn

[Addissimo]

My car was running for 6 months when my problem started. It had nothing to do with my wiring, it would have happened if I still had the m20.

[e30Matt]

Fuel pump wiring? Possibly a fuel pump going bad?

Edit: Woops, missed the post. I would check your wiring again, though.

[lukasbmw]

Well, I'll be damned. It was the MAF.

Since it was eaisest to check I messed with it first.

I just unplugged it and the car ran (very rich, but it ran). I took the element out, cleaned it off, and put it back in. Car seems normal again. Thanks guys...

[Il Duce]

my m20 was doing a very similar thing, i replaced the air filter, and it ran like a champ after that. it was a very frustrating problem, i would mash the pedal to the floor, and it would choose to accelerate when it wanted. *knocks on wood* i havent had any problems since i replaced the air filter though.

[SchnellerVert]

Told you so.....Worked on a car with identical symptoms, Plus and Audi with identical symptoms.