Engine Surges After Plug Change
Thread Starter
Burning Brakes
Joined: Dec 2001
Posts: 1,244
Likes: 13
From: Laguna Woods, CA
Engine Surges After Plug Change
About 3 weeks ago I changed plugs on my dead stock '00 FRC from the originals to NGK TR55s. The original plugs were each gapped at 0.057" and the TR55s were gapped the same right out of the box, so I left them there. As I've been driving, I've noticed that the idle is lower (around 700 rpm) and hunts and wanders, whereas before it was rocksteady at 800. Also, at steady throttle openings, there is an annoying surge that wasn't there before. I've checked for codes, there are none. I did a couple of dyno pulls and, other than the AFR dropping into the 11.9-12.1 range, there was no indication of a problem. But the engine didn't do this before. I checked to see if there were any hoses off the TB/MAF/air filter: Nope.
I'm thinking that the gap is the problem. I think I read somewhere that Chebby changed the recommended plug gap. So:
1) anyone else have problems running TR55s @ 0.057"?
2) is there a newer, different gap from the 0.057" that left the factory on '00s?
I checked the archives, but most folks had mods, so...
Regards,
Garibaldi
I'm thinking that the gap is the problem. I think I read somewhere that Chebby changed the recommended plug gap. So:
1) anyone else have problems running TR55s @ 0.057"?
2) is there a newer, different gap from the 0.057" that left the factory on '00s?
I checked the archives, but most folks had mods, so...
Regards,
Garibaldi
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I ran TR-55's at .055 (as they come out of the box) with no problems.
Perhaps a loose wire? Perhaps a damaged one (from pulling on it?)
Perhaps a loose wire? Perhaps a damaged one (from pulling on it?)
Thread Starter
Burning Brakes
Joined: Dec 2001
Posts: 1,244
Likes: 13
From: Laguna Woods, CA
Originally Posted by SDVette
I ran TR-55's at .055 (as they come out of the box) with no problems.
Perhaps a loose wire? Perhaps a damaged one (from pulling on it?)
Perhaps a loose wire? Perhaps a damaged one (from pulling on it?)
Drifting
Joined: Sep 2002
Posts: 1,947
Likes: 0
From: Howell MI.
Did you re-use the wires
The wires are probably broke.
I just bought new Magnecor wires kv85 FOR HEADERS for the ls1
I changed the stock plugs and did the wires at the same time
Mine are set a .055 NGKTR55
I just bought new Magnecor wires kv85 FOR HEADERS for the ls1
I changed the stock plugs and did the wires at the same time
Mine are set a .055 NGKTR55
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