Rough power, backfiring, and sputtering

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May 20, 2012 | 04:04 PM

99z51vette

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From: Virginia Beach Virginia

Rough power, backfiring, and sputtering

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

May 20, 2012 | 04:17 PM

Lothar34

Drifting

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From: Pearland, TX

Any codes?

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

May 20, 2012 | 04:41 PM

c5vette211

Burning Brakes

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From: Tampa fl

St. Jude Donor '14

Quote:

Originally Posted by Lothar34

Any codes?

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

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

May 27, 2012 | 06:15 PM

99z51vette

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From: Virginia Beach Virginia

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?

May 27, 2012 | 06:34 PM

bumble-z

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From: Belleville Mich.

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.

May 27, 2012 | 06:47 PM

99z51vette

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Awesome sounds good.

May 27, 2012 | 07:20 PM

c5vette211

Burning Brakes

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From: Tampa fl

St. Jude Donor '14

Quote:

Originally Posted by 99z51vette

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

May 27, 2012 | 07:41 PM

99z51vette

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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.