Why would this be happening? How to resolve?

[davidleo]

I have a 1991 325ix that I have had (just about) everything replaced. However I noticed tonight that when the car was idling the engine was loping and I noticed that the engine idle was down to around 600 rpm and the head lights, brake lights, license plate lights were glowing. What would be the cause of this and what do I need to do to correct it. Is my timing off? I am puzzled. Great site by the way! Glad to be a member.....

[lifeiskaos]

what exactly do you mean by glowing? where they on? im having trouble finding a problem in your description

[Rolla1990]

I think he means the idle was low, so all the warning lights came on because the car wasn't generating enough electricity.

You probably need a tune-up.

[davidleo]

I think he means the idle was low, so all the warning lights came on because the car wasn't generating enough electricity.

You probably need a tune-up.

Just had that done! Actually the warning lights are not coming on. It is the head lights glowing. What I mean is that they are bright then they get dim. Same with the brake and plate light. Even my interior light is bright then dims. Almost in sink with the idle of the car.

[SpecM]

have the alternater's output checked

[davidleo]

have the alternater's output checked

If the output is low that would mean new alt? Or a new batt....

[Spinning Tires]

most likely a vacuum leak. the reason why the lights are fading in and out is cause the idle drops too low for the alternator to work. definitely doesnt seem related to the alternator. 9 out of 10 times someone complains about this problem its a vacuum leak. im guessing the car runs perfect off idle and may pop a Check Engine Light with an O2 sensor code at idle

[davidleo]

most likely a vacuum leak. the reason why the lights are fading in and out is cause the idle drops too low for the alternator to work. definitely doesnt seem related to the alternator. 9 out of 10 times someone complains about this problem its a vacuum leak. im guessing the car runs perfect off idle and may pop a Check Engine Light with an O2 sensor code at idle

Yeh...... It runs almost perfect when running off idle, however it lags in power off the start. It has never pop a "Check enging light" or O2 sensor code (O2 is brand new by a couple of days) The only time I see a check light flash is when I start the engine, it goes away when I press the brake.

I don't hear any vacume leaks at all.

[norcalE30]

you probably wont be able to hear the leak... check the pcv hose

[davidleo]

you probably wont be able to hear the leak... check the pcv hose

Will give update in morning

To be continued..................

[Spinning Tires]

well if you have a vacuum leak and get an O2 sensor code. its not cause the O2 sensor is bad. Its cause the vacuum leak is making the exhaust lean and therefor popping the code. ECU trouble codes are rarely straight foward

[Spinning Tires]

oh BTW the light that says check and flashes and goes away when you hit the brake isnt the check engine light

[davidleo]

well if you have a vacuum leak and get an O2 sensor code. its not cause the O2 sensor is bad. Its cause the vacuum leak is making the exhaust lean and therefor popping the code. ECU trouble codes are rarely straight foward

I checked to see if there was any vacume leak.... None that I could find. This problem is killing me!

[Adrian_Visser]

your gunna have to do more than just look with your eyes dude it can be a real bitch to track down a vac leak if you aren't really dilligent.

you need to spray something flammable onto all the connections into the intake manifold, starting fluid works, carb cleaner might, the best thing is to take a propane torch and turn it on but don't light it then hold the tip near all the connections when you hear the engine speed change (it can go up or down depending on how much flammable shit it sucks in) you have found your leak, don't forget to check the injector o-rings under the intake manifold, and the point where the oil vent tube from the block goes into the block (hard to reach)

btw norcal there is no pcv on an e30 just a vent tube from the valve cover

[davidleo]

your gunna have to do more than just look with your eyes dude it can be a real bitch to track down a vac leak if you aren't really dilligent.

you need to spray something flammable onto all the connections into the intake manifold, starting fluid works, carb cleaner might, the best thing is to take a propane torch and turn it on but don't light it then hold the tip near all the connections when you hear the engine speed change (it can go up or down depending on how much flammable shit it sucks in) you have found your leak, don't forget to check the injector o-rings under the intake manifold, and the point where the oil vent tube from the block goes into the block (hard to reach)

btw norcal there is no pcv on an e30 just a vent tube from the valve cover

Think I found it!


Culprit:

The hose that runs from the intake manafold to the black vacume in front of the valve cover behind the radiator - water pump hoses. The hose was cracked and dried up. Replaced and WOW what a difference!

Thank you to everyone that gave input.

DLL