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TUNING HELP!

Messages
10
Likes
5
Location
Whittier California
#1
Hey guys!
I purchased a pre modded and tuned car.
Car has downpipe, intake, exhaust and intercooler.

Not sure who the car was tuned by but I recently switched out the spark plugs to NGK +1 colder that were recommended to me and now the car runs extremely rough, haven’t driven it yet but now purchasing a accessport and looking for a tune.
Any help or recommendations on what to do?
 


NOVA_Ranger

Member
U.S. Army Veteran
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Location
Prince William County, VA
#5
When swapping my plugs I made the mistake of using a small amount of dialectic grease (same stuff I've used on other cars for decades) where the plug and coil meet. The car ran rough and random misfires until I went back and removed the grease. If you happened to do the same thing...

Good luck and you'll get it sorted out! If it ran ok before changing the plugs, I wouldn't focus on the tuning.
 


OP
O
Messages
10
Likes
5
Location
Whittier California
Thread Starter #6
When swapping my plugs I made the mistake of using a small amount of dialectic grease (same stuff I've used on other cars for decades) where the plug and coil meet. The car ran rough and random misfires until I went back and removed the grease. If you happened to do the same thing...

Good luck and you'll get it sorted out! If it ran ok before changing the plugs, I wouldn't focus on the tuning.
I actually did use the grease as well.
I’m going to try that, I’ve always used it so thought it would help but I guess these tiny engines don’t like it lol

appreciate it!
 


SteveS

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Osage Beach, MO, USA
#7
If the car ran fine before you changed the plugs to step colder plugs, and taking off the dielectric grease doesn't help, switch back to the type of plugs that were making the car run fine. The obsession with step colder plugs and subsequent misfiring are related.
 


dhminer

2000 Post Club
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Burlington, NC, USA
#8
I actually did use the grease as well.
I’m going to try that, I’ve always used it so thought it would help but I guess these tiny engines don’t like it lol

appreciate it!
Our engine hates grease. The shop manual explicitly states not to use it. You could tighten up the gap to .028 and see if that helps but start with removing grease and ensuring coil packs are fully seated.
 


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