Hey guys,

Any ideas would be appreciated. Here's what happend: started my 95' z34 and it warmed up for about 3 minutes and as it warmed up the rpm started to slowly dip, rise, dip rise - it did this for about 30 seconds until it dipped so low it eventually stalled out. I restarted the car 2 other times and it did the exact same thing I described above.

What does it sound like to you? There has been a check engline light on for a few weeks but I was convinced it was the egr valve setting it off because I was told it was faulty. This might be true but it wouldn't cause this to happen. Would it be a fuel pump? Fuel relay? 135000 miles on this car original fuel pump I'm sure of it. I plan to go check the engine code soon.

 

When it is dipping low, can you touch the gas pedal and save it from dying?

That's usually what happens when an IAC is faulty

 

Chichi, thanks for response.. Yes I could save it from dying if I gave it gas. In fact, I just drove it all the way to autozone to get the engine light checked and it drove fine. At idle at traffic lights it did not stall. still think it may be an IAC ?

On another note, The code that the scanner gave was: P1640 -qdm 1-failure . He cleared it but it came back. I don't think this is related to the stalling issue I had. I briefly read the code description it said something about a PCM, quad driver and inproper voltage somewhere. The wiring on the vehicle is old, might just be getting touchy?

Man I love this car, I do have my new 06 ss but I don't wanna see this die just yet.

 

I think the QDM-1 is related to the evap system, which shouldn't really affect the driving.

The IAC sometimes gets dirty and sticks, and hitting the throttle can help to try and unstick it. They aren't cheap sensors unfortunately

 

Sorry chichi, but what sensors are u referring to? the iac is a valve or is it also considered a sensor? I checked the price on that its only about 40 dollars. Evap system hmm..maybe it is related to the faulty EGR valve.

 

I guess it's a valve Idle Air Control valve. Helps with idling the car by adjusting the amount of air needed into the engine while you aren't using the accelerator to open and close the throttle body

 

Thanks again, ive looked around online regarding that code. Basically it sounds as if it is one of the more annoying codes. When the car is in motion it seems normal. It was just that one day and I had about a quarter tank left. I will see if it continues today.

 

Slugger, I was wondering if you might have found out your problem as I seem to be having same issue. One place told me might be MAS, so I changed it and still acting up and then had the same code appear on scanner. Coworker first thought might be Throttle Position Sensor which is right there by the IAC but everyone is telling me to just sell it and get something else but I would rather fix this issue.

 

To be honest with you, it stopped doing that 3 days later - so I am not too sure. I do think it must have to with a TPS however as the RPM's would start jumping until it finally just conked out. It may just be touchy and I am sure the problem will return one of these days. Ive had throttle cables replaced as they were sticking sometime last year so those were not the problem.

Lately its been okay- but when I put it in drive sometimes after starting it and letting it run for about a minute or minute and a half it, the second I step on the gas it seems like the engine is is gonna stall in that split second i touched the pedal but then it goes.

Once ive had the car running a while and on the road it runs fine. So what would that be ? Im not too sure as I am not the most mechanicly inclined person around but I would guess could very well be a throttle related problem and if not that, I dont know. If you find out please let me know.

Good luck hope you figure it out

 

I am in same boat as you though not very mechanically inclined so I am asking friends and family that know more than I do. So after work tomorrow morning I am gonna test both TPS and IAC w/ a coworker to see if they are going bad and if so will change one or both depending on results and will let you know if it changes any. I would love to go out of town but last time I took it just to the next town over to see a concert it stalled on me couple times. My RPMs would drop real low and nearly stall or would stall like it did.