missfire or something

[95undrpsi]

when I accelrate around 5000 to 5500rpms it jerks it still accelrates after, but fall on its face.
could this be plugs, wires, coil pack, tps? What do you guys think? My mods are in my profile.

 

[not_boostworthy]

when I accelrate around 5000 to 5500rpms it jerks it still accelrates after, but fall on its face.
could this be plugs, wires, coil pack, tps? What do you guys think? My mods are in my profile.

Yes
Theres a number of things that it could be, but you should start out with changing out the spark plugs to BPR6ES's and gapping them to .028. Run a boost leak test and see what happens.

 

[95blackGsTurbo]

I would check the resistance in the plug wires too. Sounds like you are getting a crossfire issue at a certain RPM and then it stops. Plugs usually affect the whole rpm range at full boost. You would notice it at 3k and up and it wouldn't clear out. Would definatly check the plugs though and test the wires. If you don't have an ohm meter you can just run your car in a garage at night in the dark and visually see if the crossfire at all. Wouldn't think it is a coil issue since it clears out after a while.

 

[Eclipsethis90]

Had the same problem a month ago. At about 4200 rpm car would fall on its face. Went and got a new set of NGK plugs and bingo, all better. Would test the wires as said above.

 

[90blacktsiawd]

Thats how i knew it was time for new plugs in my old 96. It would happen at about 5-5.5k and up. Anywhere below that was fine.

 

[95undrpsi]

check the gap in the plugs and there all good,and the resistance of my plug wires there good.

 

[90blacktsiawd]

Ok you checked the gap but did you try new plugs yet?

 

[95undrpsi]

not yet going to get some soon

 

[95undrpsi]

Could this be also because my gm maft is not hooked up correctly

 

[Eclipsethis90]

Pinging on what 90blacktsiawd said... how old are those plugs? If you are more than about six to eight months I would not even waste my time searching anywhere else first. Changing your plugs is cheap insurance to make sure you get ignition under heavy boost conditions. Running too rich will foul out a plug with a quickness. What do you mean by your mAFT isn't hooked up right? Are you saying you don't have your Maft hooked up right and wonder why it isn't running right or are you asking is there a possibility that something stemming from your MAFT install/tune that may be causing this?

 

[sweet97]

Not sure how you could not have the maft hooked up wrong unless you are talking about the RPM fine tuning wire. Mark

 

[95undrpsi]

yeah the rpm fine tuning line could it do this?

 

[90blacktsiawd]

Well are you even running the translator in rpm mode? If the answer is no then it's not because you hooked up the rpm wire wrong. Even if you did i don't think this woudl cause your problem. Without a rpm signal if you switch the translator into rpm mode it will go by airflow rather than rpm.

 

[szewczyd]

I told you a awile ago to do plugs and wires, yes the plugs looked new but who knows how long that motor was sitting. I have a set of plugs that you can have, not NGk's but they are for our cars, you can at least try em. I have no use for them..Brand new in box.

 

[95undrpsi]

fixed. I though that the Gm maft was plug and go, but it not so Me and my friends messed around with it one night and now shes golden.


Thanks Guys for the help.