99z51vette

I have a 99 Z51 135k miles today I drove to the commissary and as I was leaving I noticed poor power and a backfire after I shifted each time. Then while sitting at the light it would be a softer sounding backfire. So my thoughts are: bad gas, plugs, wires? Any thoughts

Lothar34

Any codes?

It sounds like a missfire. Check your plugs and wires.

c5vette211

Had a similar problem. Loose spark plug. hope your issue is that easy

99z51vette

So i figured out the reason. Two of the spark plug wires on the passenger were melted to the headers. One so bad that it was sparking to it. One of the wires broke off when I touched it. So I'm going to get all new wires, plugs, and not sure what else. Has anyone put heat wrap around the headers?

bumble-z

No need for heat wrap on the headers.
Buy a good complete set of GM wires & a set of heat boot/sleeves for the wires.

99z51vette

Awesome sounds good.

c5vette211

I had a wire on my old 99 that was broken and arcing to the block and had similar problems. The only way I knew was because i had to do my troubleshooting at night

99z51vette

Yeah i was looking around at the wired and noticed that two of them looked like they were melted. So i turned it on and watched it as the spark was happening CRAZY. So time to fix it. starting to realize that the engine is becoming a money pit. Might as well say screw it and drop a LS7 in it.