losiguy

iTrader: (7)

Ok heres the deal. This is my friends car. It is a 98 Camaro Z28. It has full bolt ons and a small cam. The cam came in the car when he bought it. Specs are unknown.

3 weeks after he bought the car he started getting misfires from 3000-6000RPM ONLY at WOT. Also if he goes into to high of a gear and goes WOT say at 2,000 RPM it will also misfire and backfire. Note this only happens at WOT. The car drives perfect when at part throttle.

Sometimes the car has a high idle when it warms up. During cold starts it idles fine. We checked for vacuum leaks and put new intake manifold gaskets on.

Next the gauges started doing the following on start up. Then after a few weeks it started doing this while hes driving.

When the car mis fires when he is WOT the "Check gauges" light flashes in sync with the mis fire.

Here are the videos...any ideas on the gauge problem or any of the misfiring? Thanks.

In this video you can see the lights flashing while hes driving. They are all blinking randomly. No mis fires or anything because he wasnt going WOT.

http://pictures.sprintpcs.com/share....tate=RETRIEVED


In this video you can see the lights just stopped while driving.

http://pictures.sprintpcs.com/share....tate=RETRIEVED

We have tried anything we can think of. Replacing gaskets, swapped MAFs, unplugged PCM. Please help.

Chad

losiguy

iTrader: (7)

ttttt

ArcticZ28

iTrader: (14)

Loose connections to the battery would certainly cause that. As for the misfires, could be the plugs, wires, coil packs, or even the tune.

98z28m6

i checked the battery, cleaned the terminals, and still same thing. This is my car by the way.

ArcticZ28

iTrader: (14)

Check your grounds to the block/frame?

losiguy

iTrader: (7)

Any ideas?

LS198Z28

iTrader: (5)

i vote for grounds. thes cas will go crazy when they have bad grounds

IGNANt

iTrader: (15)

im in the same **** right now... when WOT the motor misses and guages go crazy. check all your grounds cuz this may be the main cause of it, theres also a ground behind the driverside head, that may cause the guage cluster to go wacko...

98z28m6

It seems like it only does it after its been sitting for a long period of time (such as overnight). The missfire is weird also, somtimes i can pull 2nd gear and itll be fine but right when i shift to 3rd it missfires. When the car missfires it backfires also.

Thanks for the help guys!

98z28m6

Where are these grounds located on the block and frame? ttt

98z28m6

Come on, no one has any other ideas? BUMP

98redM6

iTrader: (39)

There is one ground located right above the battery. It should have two wires running to it. There is also a ground in front of the battery. Right above the fuse box there is another ground. Also I had problems with the connections in the 2 fuse boxes under the hood. I would take out all the fuses and spray them with some electrical connecter cleaner. You can get it at pep-boys, autozone, kragen, etc. If these things don't help, it's good maintenance. Good luck.