stumble and back fire

[JasonB]

When I stop at a light or stop sign and I go to take off my car has no power and stumbles, it even back fires thru the intake. It will clear up and go after a few seconds or if I give it at least half throttle when I take off. I have a warrenty on my MAF so I am getting a new one just to try it and see if that is causing it. I've had this problem for a little while now and It is driveing me crazy.
Thanks for any help.

 

[turbo6x2]

Do you have any scan tools? This would be one of the easier ways to diagnois the issue.

 

[JasonB]

I was borrowing my friends otc 4000e and could get it again. I changed the maf today and it did not help. Things ive already done with the scan tool are: reset the iac, and the tps. I have the fuel pressure set at 41. I get no codes. I wonder if my iac isnt going bad because when it does this i hear alot of air moving thru the air filter then it stops when it clears up.

 

[ragenssjgohan]

My 84 GN does the same thing sorta. When I go to start it. It will sometimes backfire and blow off some of the vaccum lines? has yours ever done this. Do you know whats wrong with mine?

 

[JasonB]

I had that happen when I first got the car a couple of times, never blew any lines off but it did backfire and die. I dont know what fixed it but all I did then was a tune up, replaced all the vac lines, reset the IAC and the TPS. Hasent done it in almost two years. Hope that helps.

 

[Turtle TR]

hows your plugs, plug wires, coilpack and module? I'm having the same probs as you posted. while disassembling my car, I found my wires leaking silicon. and I found grey spot to what might look like arching. CRAP. too late as I've been changing out my timing chain and hi-flo timing cover, and neoprene seals. I thought it was my MAF as well, then I thought it was my o2 because the car was running really rich. HTH.

 

[JasonB]

Plugs, wires, coil pack are all new within 6 months, I havent changed the module and have no idea how old it is. I will definatly check my wires though and maybe try a module. Thank for the ideas.

 

[turbo6x2]

check to make sure you don't have a crack in one of the boots almost sounds like you have one broken or burned through the wire. This will cause the issue you are having. Or I know this sucks change the plugs and wires and see if issue goes bye bye. We had brand new ones but one got just a bit warm next to the exhaust and it caused the car to run like crap. Changed them all and the issue went away. At least pull a couple plugs and let us know what they look like could be a bad plug too.

 

[6SENSE]

I think Ive got the same thing going on with my car. Stumbling, missing, and backfire from the intake. Just to make sure it wasnt detonation I turned the boost down and FP up, but didnt make a difference.
I know that Ive got a couple of cuts in one of the boots on my wires. I thought that I would be able to get away with it since Ive got those heat shield things that came on the TurboTAs over the boots (I forgot what to call them). Plus theyre 10mm Magnecors, and Im not just throwing it out because of the boot.
Anyway, check the wires like Turbo6x2 said.


P.S. Ive gone through this before with different wires. Problem was that one wire wasnt all the way down on the plug. At night you could see the spark arcing while the car was idling.

 

[JasonB]

Thanks guys ill try to get to it Wednesday afternoon and let you know.

 

[turbo6x2]

You meant I hope "thanks guys and gals right? LOL

 

[turbo6x2]

and don't forget to let us know what you find. Details I want details.

 

[JasonB]

Sorry, Thank you guys and gals! I got to work on my car today and I found a bad plug wire. Looks like it got to hot. Never crossed my mind since it only does it at low rpm. Gonna get some new wires this week. Thanks again.

 

[turbo6x2]

Thanks for letting us know what you found and good luck hope this is it and your car runs great.

 

[Turtle TR]

Man, I wish I had found that problem earlier on my car. now it's kind of in peices.

 

[turbo6x2]

Next season you'll be that much wiser. Good Luck!

 

[Turtle TR]

bump, so how's it running?