Check Engine

[oldtimer]

I thought I would post this question before I start troubleshooting.  Now and then my "check engine" light will flash, at times not even a second other times it will stay on about a second and do this several times.  When it does stay on that long my light gets brighter and head light flashes like from low beam to high beam, even my cluster lights get brighter.  I was thinking maybe the "ALT" is on its way out and not putting out the voltage as it should.  Although it seems to charge the batt enough so it is not dead for starting.

Has anyone experience this before?  Or can you point me where to start troubleshoot?  Oh yeah is there a fault code reader for this model?  Thank you.

[strad]

Yes, there are fault code readers.  You don't typically need them though, since codes can be had through the check engine light.  

http://www.pelicanparts.com/bmw/techarticles/Mult-Code_Reading/Mult-Code_Reading.htm

[oldtimer]

Thank you for the link I actually have the book.  However, when my light flashes, now it does it one's and then nothing maybe several mile later it will do it again.

[oldtimer]

An update on my dilema.  I followed the instruction to extract the codes.  I was not successful unfortunately.  Now my car "ildes" erratic" bouncing" between 500 to 1000 rpm and when the "check engine" ligh comes on it stays on for miles and does nothing else until it repeats itself for about the same lenght of time.  Has anyone experienced this.

[strad]

Usually an erratic idle is caused by a dirty/faulty icv.  The bummer for you is that you have to remove the upper intake manifold in order to clean the ICV.  

Sometimes with the code reading you have to take several runs at it in order to get the timing exactly right -- it's also possible that your throttle position sensor is faulty/not adjusted right, and as such is not telling the DME that you've hit WOT 5x in succession = no codes.  I'd take a few more runs at it first though.

[AlpineRob]

Not long ago i had a strange erratic idle as well..also my check engine light would flash here and there..I found that it was my O2 sensor..i cant say thats what is wrong with yours but it is a possibility..when the light is on...try reving the engine to a high rpm quickly to see if the light shuts off..if so, the O2 is most likely junk. even after i bi-passed the O2 sensor..i noticed a better idle, not perfect, but better..

[Jami318is]

Not long ago i had a strange erratic idle as well..also my check engine light would flash here and there..I found that it was my O2 sensor..i cant say thats what is wrong with yours but it is a possibility..when the light is on...try reving the engine to a high rpm quickly to see if the light shuts off..if so, the O2 is most likely junk. even after i bi-passed the O2 sensor..i noticed a better idle, not perfect, but better..

Did it ever run rich when the o2 sensor was bad? I have been dealing with something like this for at least 6 months.
Driving me even more crazy then I already am! rofl
~Jami~

[oldtimer]

I did some checking around with my ICV when the started to idle irraticly, when I disconnected the tube from the valve cover which is hooked up to the ICV can ran smooth but high idle.  I disconnected the cannon plug from the back of the ICV it did the same thing.  Smooth idle but high so I am going to soak the ICV with something that will hopefully will free it up.  I think the other source for my "Engine light" was my alt.  It was making noise so I removed it and had it check, the bearing on the back side was gone so the stator was rubbing.  Got the alt. rework will see when I install it back in.