Running rich; Running out of ideas

[Bimmerboy91]

ok so ive searched and searched and spent endless hours looking around my engine to find anything that seems out of order, and still have not found my problem. my car is running rich. on cold start and worse on warm starts. and sometimes it acts fine, sometimes it will almost not even run. when im driving it and give it gas, it will stumble and then when it gets to higher like 3000 rpms it starts to act a little better

ive already replaced the fuel injector o-rings on friday and did a big tune up to it about 3 weeks ago with i replaced the distributor rotor & cap, spark plugs, oil, oil filter, air filter, fuel filter, valve adjustment, and new valve cover gasket and water temperature sensor for the computer. i know some of this stuff might not help the running rich issue. and when i disconnect my ICV when its doing this, and then reconnect it, the problem will go away but then come back later on.

so im lost. what are somethings that can help it lean out? please help me out!

[kenika65]

Same thing happened to my with my 86es, it was a stuck injector. The way I figured it out was by cleaning all the sparkplugs then starting the engine for about 2min then pull out the plugs and which ever one is covered in fuel is where you have a bad injector that is stuck open.


I could have installed a different injector but decided to upgrade to 1.3M

Also take your ICV and spray it out with break clean until it is clean then hook it up with out the hoses and when it is running spray in it. this will make sure it is clean. Just so you know make sure you are out side and no one is around because break clean stinks bad when burnt.

Also the root of all your problems can be from your temperature sensor If you have not replaced it I would first thing and make sure the connection is good and clean. And check the connection under your intake for water and corrosion.

[Bimmerboy91]

ok well ive changed the temp sensor and it made no difference, and ive tried cleaning and even putting in a new 135 dollar ICV and that didnt even do a difference. i also cleaned the injectors when i replaced all the o-rings. do you know how i might be able to clean the Cold start valve?

[Bimmerboy91]

bump!

and anyone know how to clean the AFM? ive searched but really havent found the right answer.

[AndrewBird]

Basically spray it with carb/brake cleaner. The idea is to clean all the gunk out of the flap door so it moves easilly.

Bad o2 sensor will cause the engine to run rich. Could be a bad temp sensor (there are two, one for the gauge, one for the ECU). Also could be your cold start valve.

If you search, you should find a thread on how to test the o2 sensor. The other two you'll just have to swap out for known working ones and see if there is a change.

[mops]

why do you thin kit's running rich ? is it only rich idle ? ro always rich ? how can you tell ?

1st thing i would check... vacum reference line to the fuel pressure regulator. if cracked you will be rich. common fault (with all cars)

first... you should try adjusting afm by spring. that alone can lean it out. possibly your amf is broken, but i would think adjusting it will fix it. with age the spring must be getting weaker therefore afm is easier to 'open' showing more air than actually is. it's hard to adjust it right without wideband o2 gauge, BUT i would start with 2 or 3 clicks 'tighter'.

aswell on afm there's a bypass screw, but that's only for adjusting idle.

[Bimmerboy91]

At WOT, while parked, there is a lot of black smoke. and when im driving it when its all rich, my mpg gauge says im getting really bad gas mileage and it doesnt matter what gear or rpm im at or how soft im on the throttle. and when i try to give floor it when im in lower rpms to get speed, the car hesitates so much that most of the time i have to get off the gas for the car to rev up. so im getting really bad gas mileage and fuel smell all the time. sometimes the car will act good, but other times it will almost not start. and i also changed the temp sensor for the computer like a couple weeks ago. what do i open up to get to that spring or adjuster in the afm? and which way is tighter

keep the responses coming!

[mops]

At WOT, while parked, there is a lot of black smoke. and when im driving it when its all rich, my mpg gauge says im getting really bad gas mileage and it doesnt matter what gear or rpm im at or how soft im on the throttle. and when i try to give floor it when im in lower rpms to get speed, the car hesitates so much that most of the time i have to get off the gas for the car to rev up. so im getting really bad gas mileage and fuel smell all the time. sometimes the car will act good, but other times it will almost not start. and i also changed the temp sensor for the computer like a couple weeks ago. what do i open up to get to that spring or adjuster in the afm? and which way is tighter

keep the responses coming!

on top of them afm, there's a black cover. it's glued inplace (not intended to be sercvicable). you need to pry it out gently and you will see a psring there. note the current position. with a pen or something, so you can go back. you will see how the spring is mounted, so if you tighten it then it will get leaner and if you loosed it it will get richer.

check the fuel press regulator vacum feed first. from what you are saying it looks like you are getting too much fuel. But, what's the fuel economy like ?

[digger]

disconnect O2 sensor, then if no change check FPR, then if no change check AFM according to http://frwilk.com/944dme/afm.htm

[Bimmerboy91]

well usually 10 gallons will last me 2 weeks. now its down to 1 week and couple days. or a little less. like i said ive noticed that the mgp gauge shows that im getting below 15 mpg and id doesnt matter what gear or rpm im at.

can i use electic parts cleaner to clean the flap in the AFM?

[AndrewBird]

Yes, that cleaner will work.

Have you tried any of the other suggestions?

[Bimmerboy91]

yes, ive tried to run the car without the o2 sensor. and it really made no difference. i cleaned the AFM out and cleaned the two connectors that are on the engine block that feed the fuel injectors. i havent drove it since i did the cleaning but i will tomorrow. also, i have found a vacuum leak. if my idle goes up, even a little bit when im spraying around with carb cleaner, would that cause the car to run rich? if so i found one. theres a hose that goes from the intake to the valve cover, when i spray at it the idle goes up. not a WHOLE lot but you can tell.

[redhatpat]

Test the fuel pressure, sounds like it might be a faulty FPR.

[Bimmerboy91]

ok well the car didnt change at all after the stuff i did. i mean its been a bit better but still runs rich. ive adjusted the AFM spring and have watched the AFM as i give it throtte and seems to be respond pretty good, very interesting how it works. but i havent drove it since i adjusted it. so i will return with an update tomorrow.

[Bimmerboy91]

so today after i adjusted the AFM yesterday, the car really ran no different than it did. so today i adjusted it again. and i found a vacuum leak on the hose that goes to the valve cover to the intake. i ordered a new hose that shouldve came today but there was a problem so it will come tuesday or sometime then which sucks.

so when i was adjusting the AFM today, i noticed that if i moved it slightly to left the idle seemed to surge but even out. it might be surging because i have adjusted the ICV too high. which might make sense because when i when i said that if unplugged the ICV when its running rich and plugged it back and then the car ran good, when i unplug the ICV the AFM opens up and goes crazy just like the engine revs do. but then when i plug it back the AFM seems to find it place again. Anyway, i couldnt really see if the revs got better if i gave it gas because the afm moves open. so just thought id like to share that.

well tomorrow im going the pick n pull and i might pull a computer and see if that might help. i might try to clean out the cold start valve. can i use carb cleaner to clean the cold start valve? i have a FPR that i pulled last weekend at the PnP, that i will swap in to see if there is any change.

well anyone please reply! i need to fix this problem. and if i find the problem it could possibly solve your problems or future member's problems