CEL at idle, what does it mean?

[silversleeper]

My 1989 325i is still not running at 100%. I am awaiting a settlement on an AFM purchase, and planning to do my O2 sensors this weekend.

My idle is the main concern, and is likely to be fixed whenever I replace the O2 sensors I suppose. But I wanted to see if anyone had a different opinion on that.

The idle fluctuates, on occasion. Sometimes its a steady 600rpm, sometimes its at 750, other times it bounces and settles again. The problem I have is that when the car is at idle (for instance, I reach a red light and come to a stop), the CEL comes on. It goes away as soon as I hit the gas though.

I figure since the CEL is coming on, the ECU would store a code, but when I check for codes, I get nothing. Does anyone have a simliar experience?

[surebimmer]

I would bet its the 02 sensor. But would think it would store a code. Are you turn the key on then stomping the gas to the floor 5 times then count how many time the CEL blinks.

[silversleeper]

I would bet its the 02 sensor. But would think it would store a code. Are you turn the key on then stomping the gas to the floor 5 times then count how many time the CEL blinks.

No codes. I do the 5 stomp test when I turn the key to "ON" but the CEL stays steady on. It doesnt go away either, unless I start the engine. I am getting a bit fed up with it and plan on purchasing 2 new O2 sensors tomorrow.

Can someone tell me which O2 sensors to buy? I have the 4 wire sensors. Like a part number or something? Id appreciate it.

[surebimmer]

Well the E30 only was one 02 sensor so I would buy that one. Try BMA auto parts. Think the OE one is like $68 bucks.

[nando]

I would bet its the 02 sensor. But would think it would store a code. Are you turn the key on then stomping the gas to the floor 5 times then count how many time the CEL blinks.

No codes. I do the 5 stomp test when I turn the key to "ON" but the CEL stays steady on. It doesnt go away either, unless I start the engine. I am getting a bit fed up with it and plan on purchasing 2 new O2 sensors tomorrow.

Can someone tell me which O2 sensors to buy? I have the 4 wire sensors. Like a part number or something? Id appreciate it.

could be a bad TPS. if it's not working then you wouldn't be able to run a check code (switching it on and off is what activates the codes). the only thing is my car didn't throw any codes with it completely disconnected..

either that or your timing is off. you have to be quick but not too fast. I think something like 1 second for each on-off (5 times). so count 1001, 1002, 1003, etc..

[zandi]

You're timing is probably wrong to get the SEL codes.

For getting a O2 sensor you can look it up in the catalog or ask Pep Boys but you're gonna be paynig about 80-90 bucks. If you know how to splice wires you can save a lot of money and get a Mustang oxygen sensor and splice the wires, you can find taht info on www.bmwfaq.com or maybe someone will know a better source in a post below.

[surebimmer]

http://www.bosch4less.com/index.cfm?display=display_result.cfm&xmake=BMW&xmodel=325I&xyear=1989&xcylinders=L6&xsubmodel=&xliters=2.5&xfuel=GAS

68 bucks OE part.

[silversleeper]

I would bet its the 02 sensor. But would think it would store a code. Are you turn the key on then stomping the gas to the floor 5 times then count how many time the CEL blinks.

No codes. I do the 5 stomp test when I turn the key to "ON" but the CEL stays steady on. It doesnt go away either, unless I start the engine. I am getting a bit fed up with it and plan on purchasing 2 new O2 sensors tomorrow.

Can someone tell me which O2 sensors to buy? I have the 4 wire sensors. Like a part number or something? Id appreciate it.

could be a bad TPS. if it's not working then you wouldn't be able to run a check code (switching it on and off is what activates the codes). the only thing is my car didn't throw any codes with it completely disconnected..

either that or your timing is off. you have to be quick but not too fast. I think something like 1 second for each on-off (5 times). so count 1001, 1002, 1003, etc..

Everyone keeps saying do the 5 step thing, but my Haynes manual says that the 5 step method is for the E34. And for the E30's, you have to just turn the ignition ON and it should automatically spit out the codes. Either way, it doesnt work. I have tried several different timing methods.

I hope my TPS aint bad either. So far with this car, its been nothing but problems.

[surebimmer]

So how much do you want for the car? I just did the 5 stomp test on my car an 89 325i and it worked fine.

[silversleeper]

I just did the 5 stomp test on my car an 89 325i and it worked fine.

well, lemme ask this for a change, if your car is not spitting any codes, and you do the 5 stomp test, should i expect the light to still blink something? or should it stay steady on? mine just stays steady on. with or without the 5 stomps.

[surebimmer]

http://www.unofficialbmw.com/repair_faqs/motronic.html

Code 1444 means no FC stored.

[Erick]

Is the line from the intake manifold to the fuel pressure regulator connected? The same thing happened to me. CEL would come up everytime I idled. Popped the hood and saw the line.... connected it again and voila!

[pig4bill]

Bringing this up again because I have a similar problem. The idle doesn't fluctuate much but sometimes drifts lower and I get a CEL until I push the gas a little. Recently I get it also if I'm on cruise control for a few minutes. Press the gas a bit and it goes out. I noticed it only happened at higher altitudes, like 3000 feet or higher. I live at sea level and it's the first time I've had this car at higher altitudes.

I tried the stomp test with no luck. The CEL just stays on no matter what I stomp.

[SchnellerVert]

I live in NoVa do you want to borrow my Peake tool and get the codes?

[Mr.SWISS]

had the same prob

well, lemme ask this for a change, if your car is not spitting any codes, and you do the 5 stomp test, should i expect the light to still blink something? or should it stay steady on? mine just stays steady on. with or without the 5 stomps.

Had the same problem with my 89 e30 325i after I replaced the head. did the pedal test and pulled the 1222 code for vacuum leak. My CEL would pop on @ a light after 20-45 secnds and go out as soon as I pressed the gas. The vacuum leak was the tube that runs from the oil pan to the intake mani (has a spring around it ) was missing the o-ring seal on the bottom. (I must have lost it when I pulled the intake mani off)