Really Weird Idle+loss of power

[lukem23]

i had a similar problem with my 1986 325es. the PO decided to take the AFM cover off and cylicone it back on. every now and then it shutters, but i just have to get out and check the cover.

[Atreus]

perfect. thanks a lot. lets hope i get fourteen forty four'ed.

[wagonizzle]

Pull the negative terminal off the battery and let it sit for 30 mins or more. Whenever I do this, my ECU takes a few miles to 're-learn' what the car likes, but after that it smooths out like normal. For all I know this means there are problems it is adjusting to but you should have no more codes. Drive it for a bit and then do another stomp test; sometimes the check engine light will flash while driving and you may not notice it, and then a code is stored. I believe a 1444 is all clear, but I'm assuming you have a fault code list. Good luck :D

[Atreus]

im guessing afm/icv? it was throwing a code for bad afm, i just removed the whole intake and cleaned out everything and double checked the connections, one large can of carb cleaner+toothbrush

however, i did a stomp and it still gave me a 1215, which is weird because the car has been running smoothly. lowered the idle to about 800, and no more bucking/hesitation.

how do you clear engine codes anyway?

[whiltebeitel]

So, what ended up causing the issue?

[Atreus]

well, in case anyone was wondering, car has been fine. runnin like a champ, i'd like to thank everyone for their help. learned a couple of things.

thanks guys.

[Atreus]

omg. bwahahahahahah! oil cap oil cap man. god i didnt even notice that.

[SpecM]

pulled the gas cap

not the gas cap... the oil cap!

[Atreus]

update: cleaned my icv/afm/tb = car runs smoother now. did a 30 mile test run, no issues.

however, after another stomp, it still gave me the 1215....is it cleared now? how do i reset it.

[Atreus]

okay. cleaning my icv+afm now. i am using carb/choke cleaner on both. pulled the gas cap and it did stutter on me, but kept going. gonna take a shot at the TB now..... see you in a hour!

wait. will carb/choke cleaner mess up my TB if i use it on that?

[Fidhle007]

Try unplugging your AFM and see what happens too, a lot can be learned by how a motor reacts when you disconnect a vital part of it's system. As a professional tech, this is often the first thing I do to a car with weird running problems that my scan tool can't decipher.

Think of a your engine's management system like the human body/brain. We use a combination of information from various sources to function every day (sight, hearing, smell, touch) and if one of those senses were to suddenly malfunction, we'd start walking into things. Now imagine you're a doctor and your patient is mute and can't tell you what doesn't work (your car without a scantool.) If you start depriving senses one at a time and watch the reactions, you'll get a pretty good idea of what's not working or malfunctioning. It's a similar situation with a car, but slightly more complex as there are many different things that can cause similar symptoms. But then again, that's why we charge $75 an hour...

A quick vacuum leak check (if you don't already know this) is to remove the oil cap while the motor is running. A sputter or possible stall is good, no change is indicative of a leak or AFM issue.

Good luck and keep us posted!

[SpecM]

1-2-1-5 here i come. maf/afm=same thing?

sort of... close enough for the purposes of this thread.

AFM codes can also be vaccum leaks in disguise, tho!

[Atreus]

1-2-1-5 here i come. maf/afm=same thing?

[Atreus]

perfect, i'll do a stomp test and go from there. thanks a lot for the advice/pointing me in the right direction everyone. stomp test here i go.

[SpecM]

Unhooking your ICV will cause a huge vacuum leak and kill your engine

not so sure where you got that idea

to the OP: the AFM sit above and to the right of the air filter housing