Engine dying during idle

[lanier63]

I just bought a Q45 a couple of months ago. Drives great but the other day I came to a stop sign and my engine died. I started the car back up and it had some trouble idling. Once I am driving it seems ok but when I stop the engine rpm is barely fluttering at 500 rpm and does dip just above 0 rpm. It has been doing this ever since and I was wonder if anyone had any suggestions on how to remedy this. The car has been great up to this point and hope I did not get a lemon.


Thanks,

lanier63

[lanier63]

BTW it is a 1994 Q45

[Piston1047]

well your lucky, you 94 Q is not a lemon, I thought the same about my 94 Q i bought about 4 months ago. it had the same problem as yours. it would idle inconsistently and sometime cut of when i accelerated or stopped abruptly, i found that the problem was my mass air flow sensor connector. the sensor and wire were loose and this intern would cause the engine to cutt off. The best way to test this on your car is to go under the hood and gently touch and shake the wire if the engine shows any idle response or shuts off it is the problem.the dealership told me that they would replace the connector for 300 dollars since i just bought the car and i have experience with working with cars i felt that was too expensive, so anyway i took the plastic insilation off the connector and found the loose connection, one of the three connector wires was having trouble remaining in the connector socket. so it wedged the wire in the socket with a small skrew. It worked and since then i have driven my car from Maryland to Texas with no sighn of a problem and 300 dollars to spare. i hope this helps, if you have any questions feel free to respond back

[do_care]

i just bought a 1991 Q45 and drove it from houston to new orleans and it started to do the same thing on me. i brought it to the dealer and he didnt find a thing wrong with it. could this be the same problem as your '94? (mass air-flow sensor)

btw it wont go above 3000rpm's w/o spitting and sputtering.

[maxnix]

Any buzz from behind the seats? Changed the fuel filter recently?

Check the MAF connection. It was updated mid 1994.

If your TB, plenum, IAC or EGR vlaves or pathways are less than pristine, then you will have problems no matter what else is perfect.

Assume air filter is new also?

Are you sure you're not in failsafe mode due to some other problem?

If it is a 1993 or earlier, better check you timing chain guides ASAP.

www.nicoclub.com

[Texasoil]

Stalling at idle, low idle speed may/usually caused by sticking idle air controlled (AAC) in dealer speak. Its located on the top back of the engine--and regulates auxilary air flow to control the idle speed. If you disconnect the brown electrical connection and engine speed does not change--the AAC is not working--and is usually stuck--requiring removal and cleaning with carb/choke cleaner. Sometimes the throttle position switch (on the throttle shaft) fails and the idle control circuitry is never activiated and will cause this condition also.

If the engine also will not run well at higher speeds, it may be the mass flow sensor (MAF)/connector up by the air cleaner. Check that connection carefully by wiggling and pulling. Any change in engine operations indicated a poor connection there. Unplugging the MAF (you have to lift up the fine spring wire lock holding the plug onto the MAF) should result in engine surging,stumbling, etc.

I have found the cure to poor electrical connections is CL-85 (this is the Borg-Warner number), a real 'space-age' contact enhancer that works permanently. Available at better auto parts stores (usually by order only) since its about $58 for the smallest size (which will last a car owner forever)