check engine light - United Bimmer Community

**mzbmw325i** · 05-09-2008, 03:43 PM

the check engine light on my 325i is on all this week, it goes away for few seconds and comes back on. i tried the stomp test, but light doesn't even blink, rpm is fine, car runs ok, for a 200+k mile car. what could it be

? thanks

**Exilion** · 05-10-2008, 07:49 AM

When was the last time you changed the oxygen sensor.Usually the check engine light means check your emissions control system.

**az3579** · 05-10-2008, 08:52 AM

Look at your check control panel. Are there any LED's lit? If there are, those can trigger the check engine light to come on. If you press the "Check" button and let go, the check engine light should go off if the check engine light is on because of one of those items. If not, then I would agree about the emissions system.

**elsabor67** · 05-10-2008, 11:07 AM

I would also say the O2 sensor. Go get a new one.

**delmarco** · 05-10-2008, 12:02 PM

O2 Sensor!!!
Change it! Now!

**peterkdenny** · 05-10-2008, 01:08 PM

Can't you go to autozone or something and have them run the codes on it? or is that just on obd II cars?

**mzbmw325i** · 05-10-2008, 07:46 PM

I changed the oxygen sensor 2 yrs ago, autozone can't run check on older bmw's. on the top panel i only get a warning for the windshield fluid is low, i doubt that will trigger the check engine light. i always press on the check button on top once i start and get going with the car.

the thing that puzzles is me is that the stomp test does not trigger the check engine light to release any codes. i guess i will keep going for now.

**elsabor67** · 05-11-2008, 11:07 AM

The check control panel only lets you know of things like the fluids and any burnt lights. That is wierd that it won't throw you a code. Do you do it with the key in the "on" position (Not trying to insult your intelligence) without starting the car? It won't even display the "1444" everything is good code? If it's not even coming on change your bulb on the cluster then try it again cause that sounds wierd. Good luck.

**az3579** · 05-11-2008, 09:47 PM

Quote:

Originally Posted by elsabor67

The check control panel only lets you know of things like the fluids and any burnt lights. That is wierd that it won't throw you a code. Do you do it with the key in the "on" position (Not trying to insult your intelligence) without starting the car? It won't even display the "1444" everything is good code? If it's not even coming on change your bulb on the cluster then try it again cause that sounds wierd. Good luck.

Actually, those lights will throw a check engine light. My coolant sensor is shot, so that's on all the time and occasionally my brake light LED comes on but the brake lights work fine. Any time my check engine light is blinking, I press the Check button and the Check Engine light disappears.

As for the stomp test, I've tried it countless times with no avail. I remember reading somewhere that it only works on certain Motronic systems. I think there's an older version that it does not work on. His might just be that older version.

What year is his car? Maybe he confused the 325i with the 325is? (Seems unlikely the 1991 325i would have the older version Motronic system)

**Alex 1993 525i auto** · 05-19-2008, 10:12 AM

Check engine light is often due to vacuum leak. Check for a leak at the vacuum pipes, that go around the intake manifold, crankcase ventilation, intake air booth. Also check the intake manifold gaskets and throttle body gasket. You can spray throttle body cleaner on those with the car at idle, you will hear a change in idle if there is a leak.

**elsabor67** · 05-19-2008, 01:38 PM

Quote:

Originally Posted by az3579

Actually, those lights will throw a check engine light. My coolant sensor is shot, so that's on all the time and occasionally my brake light LED comes on but the brake lights work fine. Any time my check engine light is blinking, I press the Check button and the Check Engine light disappears.

As for the stomp test, I've tried it countless times with no avail. I remember reading somewhere that it only works on certain Motronic systems. I think there's an older version that it does not work on. His might just be that older version.

What year is his car? Maybe he confused the 325i with the 325is? (Seems unlikely the 1991 325i would have the older version Motronic system)

Okay, I know about the one on the center that tells you when the oil level and bulbs and things like that go bad and you see the flashing check light. The one i'm referring to is the one that is located on the lower left of where that check in the center is. That is the one that gives you the codes and says "check engine" on it.

Also check this out: http://www.unofficialbmw.com/repair_faqs/motronic.html

This page has the fault codes for earlier model BMW's like ours that don't come out on the check light but on the "check engine" light. If you have any questions just shoot me a PM. Good luck

**BMWFreak** · 05-30-2008, 02:20 PM

Usually when your check engine light is on you should check your engine hahaha. But if theres nothing wrong with it there could b a glitch or short in the wiring. My brake lining light on my car flickers on and off its kind of annoying but its not worth tearing the whole dash board apart to find the problem.