Have a problem after changing spark plugs
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Joined: Feb 2011
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From: Broussard Louisiana
Have a problem after changing spark plugs
I just changed my spark plugs to the NGK Plugs and i gapped them to .60 like the sticker on the hood says they need to be and it idles fine but i took it out to get on it a little and see if it had more power and it is like popping out the tail pipe and has a strong smell of carbon. A friend went with me to listen to it he is going to school to be a mechanic and he said it is built up carbon on the pistons.... He said that when you change plugs from old ones the computer has to learn them because they fire hotter than the old ones and also it will have to burn off excess carbon that has built up on the pistons and valves....does this sound right? I'm worried because i expected it to run better not back fire or surge like it is in WOT. Like i said it idles fine and i know i didnt out the wires back on wrong or anything like that. suggestions? thanks
Melting Slicks
Joined: Jun 2012
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From: Oceanside California
The TR55's are meant to be gapped at .055" hence the TR(55). And I found them to work best at .050". So thats where they are at for me. The .060" was changed to .040" for the LS1. But I do think that was overboard. Try running .050" and see what you think.
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From: Broussard Louisiana
Ok so i should go to .50 gap? Mine are the NGKR V-Power plugs not the NGK55
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From: Broussard Louisiana
Here's what E3 says about there plugs....
E3's DiamondFire design forces the electrons to form the plasma channel faster and stronger. This reduces ignition delay for an improved electrical-to-chemical energy transfer that provides a faster flame kernel for more complete combustion, better power, and higher fuel efficiency.
E3's DiamondFire design forces the electrons to form the plasma channel faster and stronger. This reduces ignition delay for an improved electrical-to-chemical energy transfer that provides a faster flame kernel for more complete combustion, better power, and higher fuel efficiency.
Instructor
Joined: Apr 2012
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E3s are also a gimmick. The carbon story is not plausible so much. Imo, you've closed a gap somehow, opened a gap somehow, don't have one torqued, or tweaked a plug wire. Just recheck the installation.
Also vpower = tr55
Gapping these cars is simple.... the lsx ignition system doesn't really care when a car is stockish. .055 is probably what the plugs gaps out to from the box, roll with that.
Also vpower = tr55
Gapping these cars is simple.... the lsx ignition system doesn't really care when a car is stockish. .055 is probably what the plugs gaps out to from the box, roll with that.
Last edited by Summer wolf; Apr 7, 2013 at 10:50 AM.
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From: oregon
which plug do you have? if it doesn't say tr5 or tr55 on it you have the wrong plug. running the wrong heat range can be bad news bears.
if you have a tr5 i'm a big BIG fan of smaller gaps since they are so much more resistant to detonation. these engines are so easy to make power with as it is 1-2hp over knocking isn't worth it imo
.040 would be where i would gap, .050 at largest.
there is a new GM service bulletin calling for .040 on the ls1/ls6
if you have a tr5 i'm a big BIG fan of smaller gaps since they are so much more resistant to detonation. these engines are so easy to make power with as it is 1-2hp over knocking isn't worth it imo
.040 would be where i would gap, .050 at largest.
there is a new GM service bulletin calling for .040 on the ls1/ls6
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Burning Brakes
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From: Florence SC
.060, and maybe even .045? Please share those results.
Race Director
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From: oregon
just was thinking about this and i've never seen gap cause this. i have seen bad plugs or misfiring wires do it though. did you drop any of the plugs that you put in? are you sure they are tr5 plugs? did you pull a wire apart when removing? running on 7 cylinders could cause all kinds of popping and weird idle issues
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From: Broussard Louisiana
just was thinking about this and i've never seen gap cause this. i have seen bad plugs or misfiring wires do it though. did you drop any of the plugs that you put in? are you sure they are tr5 plugs? did you pull a wire apart when removing? running on 7 cylinders could cause all kinds of popping and weird idle issues
Safety Car
Joined: Apr 2007
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From: SoCal CA
which plug do you have? if it doesn't say tr5 or tr55 on it you have the wrong plug. running the wrong heat range can be bad news bears.
if you have a tr5 i'm a big BIG fan of smaller gaps since they are so much more resistant to detonation. these engines are so easy to make power with as it is 1-2hp over knocking isn't worth it imo
.040 would be where i would gap, .050 at largest.
there is a new GM service bulletin calling for .040 on the ls1/ls6
if you have a tr5 i'm a big BIG fan of smaller gaps since they are so much more resistant to detonation. these engines are so easy to make power with as it is 1-2hp over knocking isn't worth it imo
.040 would be where i would gap, .050 at largest.
there is a new GM service bulletin calling for .040 on the ls1/ls6
I found .040-.050 on a stock motor works best. I run .035 in my cammed motor.The Idle is fine and also when just driving normal down the road it purrs along like it should. It only starts popping and has the strong carbon smell when I floor it. I didnt drop any of the plugs or anything like that and i was careful pulling the plug wires off so i dont think it is that...might be but i dont think it is
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From: Broussard Louisiana
Ahhhhhh Ok, Yep i think this could be the problem....lol I was re-gapping them to .45 and looky what i found. Guess I need to get laid or something cause it looks like i Gorillaed it in there and snapped it. I went ahead and regapped all them to .45 and used one of my old plugs on this cylinder and it runs like a top now. Thanks for you guys help i appreciate it.
Race Director
Joined: Jan 2008
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From: oregon
i thought so. that's very typical of a cracked plug. i once dropped one on a concrete floor and had the same symptoms. also found the same problem. mine stumbled at idle though. then again it was on a 4cyl which is MUCH more obvious when a cylinder is down
Melting Slicks
Joined: Jun 2012
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From: Oceanside California
You again.. why would I have said it if I did not try various gaps? I found where the car idles best and maintained the widest gap possible. Some people can get away with more. But .050" makes the car run quite smooth.
Last edited by NukeC5; Apr 7, 2013 at 06:49 PM.
Melting Slicks
Joined: Jun 2012
Posts: 3,163
Likes: 6
From: Oceanside California
Ahhhhhh Ok, Yep i think this could be the problem....lol I was re-gapping them to .45 and looky what i found. Guess I need to get laid or something cause it looks like i Gorillaed it in there and snapped it. I went ahead and regapped all them to .45 and used one of my old plugs on this cylinder and it runs like a top now. Thanks for you guys help i appreciate it.
Melting Slicks
Joined: May 2000
Posts: 2,498
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From: Brentwood TN
It isn't the gap. 0.005" won't cause what you describe. You found the cracked plug. It can also be the spark plug boot didn't seat. It is necessary to "burp" the boot when you put it back on to get the trapped air out. I inserted a small wire tie up into the boot and put the boot with wire tie over the plug, pushed it into place and then removed the wire tie. You can probably get by with this but the first try when I put in my new plugs didn't get the air out and I had a misfire.
Charlie
Charlie
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From: Broussard Louisiana
It isn't the gap. 0.005" won't cause what you describe. You found the cracked plug. It can also be the spark plug boot didn't seat. It is necessary to "burp" the boot when you put it back on to get the trapped air out. I inserted a small wire tie up into the boot and put the boot with wire tie over the plug, pushed it into place and then removed the wire tie. You can probably get by with this but the first try when I put in my new plugs didn't get the air out and I had a misfire.
Charlie
Charlie