bad ground?

[acolella76]

I was driving around today and my car started stumbling at idle for no apparent reason. While it was stumbling, all of the lights started to dim and a few of the lights on the dash flickered. Once I revved it up the lights became bright again and then it just suddenly died. A few minutes later down the road it just started to buck for no reason in the low RPMs but it is completely fine up high.

Also, it REEKS of gas on start up sometimes even though I don't have any fuel leaks. So do you guys think there is something electrical going on or should I check out my FPR and injectors?

[paperplane94]

Sounds like your alternator is going...

Time to pull out the 'ol DMM!

Tell us what your running voltage is so that we can better diagnose the electrical problem.


The other part about the fuel smell may be related but probably not. Most likely you are running rich or your FPR may be leaking.

[HR2L]

Voltage Regulator in the Alternator going po0p. It could be a bad ground as well, or a combination of both. Like Paper said, might be time to break out the ol' DVOM and start testing. ;)

[acolella76]

Thanks guys... I checked the battery and alternator and there were no signs that the alternator was going out :(

[yert315]

No fuel leaks but it reaks of fuel? Something's not right.. I would double check for leaks around the engine and the pump under the back seat

[acolella76]

Only smells like fuel in the engine bay on a cold start up. All fuel lines are new

[borise30]

A Dying crank position sensor me thinks

Have known similar symptoms prior to no start

[bmwguy325is]

You may have an injector the gets stuck.

[paperplane94]

Did you check the vacuum hose off of the FPR like I said to?;)

Oh wait I didn't tell you to do that, sorry my bad.


Find you Fuel Pressure Regulator and then find the vacuum hose coming off the top that leads to the intake manifold. Pull the hose off and smell the inside of the hose for any scent of fuel.

If she stinks the FPR needs to be replaced.

Do this test above, but I still think that the problem is electrical.
You said you checked the alternator, how did you do this exactly?

[acolella76]

I think it might be both electrical and the FPR, actually. lol. I will go smell the FPR and I am probably going to check the alternator again. Found out my multimeter doesn't work very well lol I will get back to you guys.

Boris, the CPS is brand new as are all the other sensors on the car. I recently converted to Motronic 1.3 and thought it would be a good idea to buy all new sensors, fuel line, and vacuum line

[paperplane94]

You know I meant that if you smell fuel in the vacuum line replace the regulator, not the vacuum line.


Jus' checkin ;)

[broke30]

Sounds like coil to me. Smell of fuel is unburnt due to no spark. And studdering fits as well. I've had this problem once before. Voltage draw from the coil can cause all of your electrical problems as well. There is a procedure to test the coil but you're just as well off buying a new one.

Max

[bastianshaw]

Sounds like coil to me. Smell of fuel is unburnt due to no spark. And studdering fits as well. I've had this problem once before. Voltage draw from the coil can cause all of your electrical problems as well. There is a procedure to test the coil but you're just as well off buying a new one.

Max

Time for MSD?
check the fuel rail

[acolella76]

I bought a new DMM and I'm going to test all of the harness connections, DME power/ground, and coil voltage. Should I be seeing 12v at the coil or what? I can't seem to find out how to test the coil.

Regarding the FPR, I sniffed the hose and smelled nothing. I even tried to suck fuel out through the hose and still nothing. So I'm guessing that the FPR is good and my problem is electrical.

Also I read somewhere that if the tach needle drops to 0 while the car loses power its due to the DME timing, if it doesn't drop then its fuel related. Well my needle will bounce all across the universe. From 0-4k sporadically and the econometer will wave to me as well.

[jlevie]

Random fluctuations in the tach and econometer that aren't associated with dramatic power loss are probably caused by problems in the cluster, it's power feeds, or it's ground.

The coil positive should have system voltage on it when the ignition is switched on. You can check coil resistances, but in most cases a coil problem results in no spark at all.