E30 Track Kar

[Jake]

OK, I had an Eta with fuel issues so let me clarify some of BJ's points.

1. A bad AFM will absolutely cause poor idle. Mine would lope and stutter and generally run like ass. Find someone selling a used one. Brand new they are $500. Think I paid $40 for mine.

4. There is a "transfer pump" because the fuel tank is a saddle-style. Could be a bad pump and you do have two.

I got mine to run "better" - it would rev all the way to redline fine, sometimes - but was never perfect. It had a lot of fuel delivery issues. I think Mike (who bought it from me) was able to make it better still, but not sure what he did. Look for my 325e project thread and see if you can glean any insight there.

[Maengelito]

I'm not sure that it's fuel. But I can't get the rev over 2k and I have to give it more fuel for it to even hold an idle. I changed all the spark plugs already too.

This is a ~25ish year old BMW, right? I'll bet its one of the 5000 rubber vacuum hoses is cracked and letting in unmetered air.

[D_Eclipse9916]

I'm not sure that it's fuel. But I can't get the rev over 2k and I have to give it more fuel for it to even hold an idle. I changed all the spark plugs already too.

This is a ~25ish year old BMW, right? I'll bet its one of the 5000 rubber vacuum hoses is cracked and letting in unmetered air.

Any 25-ish year old car, first thing is to go through the car and replace allll the rubber.

[ispoonwithmugen]

Alright, I'll start going through all the rubbers... yayyyy, haha.

[ispoonwithmugen]

Still dicking around with it. I had replaced the transfer pump already and that was bad. I do have a regular fuel pump I can put in as well. I can't seem to find any cracks in any of the hoses. Would they be visible? Jake I remember you saying you had a good website for getting a certified IACV?

[ispoonwithmugen]

Okay so I have it "narrowed" down to these:
Vacuum leak
Clogged injectors or bad wiring
Idle air stabilizer valve (hoses as well)
Coolant temp switch and sensor
Large intake air duct
Small hose between intake manifold and pressure regulator
O ring on injectors
Ignition and distributor cap
Grounds
02 sensor? I was thinking I could rule that out since it won't kick in till the car is at normal temps.

Any thoughts on these? Can I eliminate anything or should I include some other things?

[Sully]

Did I miss it in the thread or fuel filter?

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[ispoonwithmugen]

I changed the fuel filter already. I believe there is only one (under the car on the drivers side).

[JustinG]

Smell/see fuel around the injector? If not, safe to rule out the o ring. But if you are pulling the injectors to test them, I'd replace the o rings.

[ViPER1313]

Smell/see fuel around the injector? If not, safe to rule out the o ring. But if you are pulling the injectors to test them, I'd replace the o rings.

For the top rings that might be the case, but for the bottom rings that's not true at all. The bottom rings can leak unmetered air and make the car run like hell, but you won't see external signs of the leak. Try pushing each injector firmly towards the head with the car running or spraying some carb cleaner at the base of each injector and see if the idle changes.

[ispoonwithmugen]

I was going to pull the injectors anyway. So while I'm in there I might as well change both O rings before throwing it back together. I checked all the grounds and came up with nothing. Same with all the common vacuum leaks places. I can't find my dad's voltmeter or whatever it's called so I'm waiting for him to get home to try and check over everything with that as well.

[ispoonwithmugen]

So I've limited it down to the O rings/injectors or the distributor. Finally bit the bullet on a new battery as well. Advance wanted 156 after the core! Now she is starting every time but it's still god awfully rough. When I floor it it still won't go above 2k RPM's. All the plugs are new so I'm thinking maybe the injectors are clogged up? I'll try and get a video up tomorrow.

[Sully]

I'm pretty sure mike bought a injector overhaul kit for Jake's old e30. Maybe try that? Actually, NASA guys chime in, doesn't Xavier do something injector related? Grid to Announcer (DJ), whats that crap you're always saying on the microphone?

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[D_Eclipse9916]

I'm pretty sure mike bought a injector overhaul kit for Jake's old e30. Maybe try that? Actually, NASA guys chime in, doesn't Xavier do something injector related? Grid to Announcer (DJ), whats that crap you're always saying on the microphone?

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In all the days of me trying to get shit to run, I have never once had a car drive like complete shit/not start with "clogged" injectors. But ya never know. Dead injector just makes one cylinder not fire, (put a screwdriver on each injector and make sure they are each clicking.

Injector Pulse can fix your flow :wink:

okay, we need to start over with diagnosing. Can youi get the car to at least run? Get it running, if you have to hold the throttle, grab a friend. Hold the throttle or idle steady and pull each spark plug wire/coil pack individually. If the sound of the motor changes, that is good. That spark plug/coil pack is working. Go slowly by each cylinder. If they all do the same thing, you have an ECU/MAF/Ground/Vacuum issue.


BTW, easy way to test your injectors. Find out their flow rate, find a large metering jug (or even more ghetto, zero out the weight of an empty milk jug, and use weight to calculate how much fuel). Jump each injector and test them out against each other/spec into the jug. (use the clock and spray for exactly 15/30/60 seconds, all up to you, but calculate based on time) If everything works, throw together with new o-rings in.

Move on to vacuum leaks. Start by spraying carb cleaner all around the intake manifold/injectors etc (dont just spray everywhere, spray certain areas first. (if the car is even idling enough at this point).

Have you OHM tested your TPS/Coolant Temp sensors? Try that next.

Does the car have a schraeder valve on the fuel rail? Borrow someone's fuel pressure gauge and check idle/throttle fuel. Fuel pressure should be lower and stable at idle. Should rise with throttle.

Do all these before spending any more money please. Give me a call, where is this car?

[D_Eclipse9916]

OT I know, but Garrett, did you still want to come down and crew/watch chump car? We are headed down 95 and passing by Richmond around noon-12:30 on friday, returning in the afternoon sunday. I will have room in my truck if you wanted to ride along.

[ispoonwithmugen]

Car will run every time if I hit the throttle. Car is in Spotsylvania (right off Fredericksburg). I have OHM tested Coolant temp sensor and switch but they were both operating good. I'll try the plug/ injectors tonight to see what I can get out of there. I'm also unsure of the valve on the fuel rail. I'll check the Bentley manual and let you know. As for helping I think it's out of the question right now. As much as I want to I just got my wisdom teeth out last Thursday and I'm having complications. I have a check-up tomorrow so I can ask (and the guy is a BMW guy, he preordered the new M4) but he was saying I would need 2 weeks for recovery so we'll see.

[BLINGMW]

before tearing it apart and catching yourself on fire, I haven't seen mention of actually testing the vacuum... did you do that? Pretty easy and would check one potential problem off the list. I also don't know why you no longer suspect the AFM, it's a pretty common source of problems and would be high on my list. Swapping with another known good(er) one would be best as they're hard to test.

[ispoonwithmugen]

Hm, what's the easiest way to test for vacuum? What DJ said with a carb cleaner? I seem to have left AFM off. I'll see what I can do with getting my hands on a better one but I'd prefer to knock all the free(er) things off the list first.

[BLINGMW]

nah man that's f-ing crazy, I think DJ wants to get you killed. Vacuum test gauge. Maybe you can even borrow one from Advance or AutoZone. Otherwise I think they're like $20. You're welcome to borrow mine, though I'm in Roanoke.
I don't remember if the M20 has vacuum test ports on the manifold, but I never had trouble finding a small hose to disconnect (like to the FPR for example) and connect the gauge.

[ispoonwithmugen]

I'll probably just go buy one. I'm going to need it in the future anyway (at least that's what I say to justify 99% of the things I buy). If it doesn't have said ports then I just stick it in a small hose? That sounds a little bit easier.