For more than 5 secs...

Guys, I have had trouble with my car not staying running...I am actually an Impala guy, but I cannot seem to really get any help so I am coming to you for help...

You can read this for some background info...
http://impalassforum.com/noncgi/ulti...;f=33;t=004941

What the hell can it be? I know the cars are a little different, but any help would be appraciated!

Troy

 

ttt

 

Sounds like what can happen if the MAF is unplugged or no power. Check for voltage on the pink wire when the key is ON (assuming your wire colors are the same).

You might also want to put a fuel pressure test gauge on it to see if the fuel pump is running after the engine fires. If not, that's going to be more you will have to track down.

 

Fuel pressure is good, does not drop, so I know that the pump is not cutting out. IF I unhook the MAF, the car SHOULD run in open loop right? But it doesn't even do that, so I am thinking that it is not the MAF...If you guys read the post, I talk about the previous owner having a system or something in the car and when he ran the power cable, it looks like he might have hit the bundle of wires that runs through the firewall.....I don't know how similar our cars are in this repsect, but does anyone know what these wires are? It looks like the pink wire on the bottom side of the bundle, closest to the firewall may be damaged. Could this cause a problem? What about the computer? Any possibilities that it may have gone on me? Shorted out?

This thing is REALLY bugging me now and I just want to get it done.

Thanks,
Troy

 

It should run with the MAF unplugged, yes.. [at least mine does..]

 

mine runs with the MAF sensor unplugged. I however never unplug the sensor with the engine running. have you turned the engine off to unplug your MAF first?

Also check to see if any of those damaged wires go to the PCM

Marvin

 

One time when I forgot to plug in my MAF, it would just start and die. I never experimented with it after that. I am not disputing what others said, just relating my experience so you don't think I said that without some reason behind it. I also said "can" and not "will" on purpose.

 

that sounds like the factory anti-theft system is acting stupid. when the can is in anti-theft, it will only run for maybe 3-5 seconds then the PCM will kill the injectors and the engine will die of course. Get one of them diagnostic light modules you plug into the injector harness, crank the car, hold the throttle to 2000RPM and look at the light, see if it stops flashing.

 

Thanks for the replies...

We tested everything today. Brought a spare MAF, IAC, MAF harness and to no avail. The car is throwing a code of Mass or Volume air circuit something or other even with the new MAF, so I am starting to think that maybe the computer is fried. A GM tech said that he has seen VERY rare cases where reconnecting the bat. will cause a spike in the computer and cause it to do weird things. Going to try a new computer, possibly switch over to OBD1, which will also rule out crank possition sensor, just in case....

If it is something like the VATS anti theft, how do you fix soemthing like that?


Thanks guys!

Troy

 

If you have a MAF DTC (please post the exact number) you might want to test the pink connector wire for power when the key is ON.

 

yeah fix the MAF sensor circuitry before getting a PCM

 

Well I am bringing this back to the top guys, cause I have some free time again to work on the car...

What do you mean by the MAF DTC? As far as the circuitry, we tried three different MAF sensors, and two different harnesses. Would this not show the circuitry to be bad?

If not, I assume that I test the wire by using a multimeter right?

Thanks guys,

Troy

 

A 'MAF DTC' refers to a MAF 'Diagnostic Trouble Code'[DTC] as obtained by a diagnostic scan etc..
This would probably show as a 4 digit # with your OBDII..