Could improper plug gap on NGKTR55 cause code p0300?
Thread Starter
On The Tree
Joined: May 2012
Posts: 160
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From: Port St. Lucie, FL
Could improper plug gap on NGKTR55 cause code p0300? Hey guys,
Just kind of....going down the checklist to find the reason for my P0300 misfire codes I keep getting after my header install.
I used the NGKTR55 plugs, along with MSD wires. . I believe he gaped the plugs at .35 or .40....are these plugs supposed to be in the .50 to .60 range?
When I got the P0300 code the first time, it turned out to be a number 8 plug cracked, and the same wire for that cylinder was not on completely. I was with my friend when we took out that plug and replaced it (what a pain in the *** to get to), but I am not sure if he had gaped that one or just put it in with the stock gaping.
Just wondering....could something like this cause a random multiple misfire, code P0300? (Not gaping to how the spark plugs should be, possibly different gaping on 1 of them) I drove the car for hours and there was no SES flashing, but all the sudden it came back....usually happens under load in 4th gear but also happened in 2nd.
My buddy is going to get his friend's HP Tuner, so we could get an idea of just what exactly is going on-- it's all guessing at this point. Figured I'd ask you guys, process of elimination lol
Thanks for any replies, this car sounds great but I get very weary of driving anything with a misfire being reported....don't want to blow my engine lol I'm still paying her off
Kenny D
Just kind of....going down the checklist to find the reason for my P0300 misfire codes I keep getting after my header install.
I used the NGKTR55 plugs, along with MSD wires. . I believe he gaped the plugs at .35 or .40....are these plugs supposed to be in the .50 to .60 range?
When I got the P0300 code the first time, it turned out to be a number 8 plug cracked, and the same wire for that cylinder was not on completely. I was with my friend when we took out that plug and replaced it (what a pain in the *** to get to), but I am not sure if he had gaped that one or just put it in with the stock gaping.
Just wondering....could something like this cause a random multiple misfire, code P0300? (Not gaping to how the spark plugs should be, possibly different gaping on 1 of them) I drove the car for hours and there was no SES flashing, but all the sudden it came back....usually happens under load in 4th gear but also happened in 2nd.
My buddy is going to get his friend's HP Tuner, so we could get an idea of just what exactly is going on-- it's all guessing at this point. Figured I'd ask you guys, process of elimination lol
Thanks for any replies, this car sounds great but I get very weary of driving anything with a misfire being reported....don't want to blow my engine lol I'm still paying her off
Kenny D
Doubt it. My son's Crown Vic P.I. started getting misfire codes, we pulled the plugs and they were worn to the point of 0.125" - 0.150" gaps, yet still firing "most" of the time, even at that! I don't think the Ford COP ignition is that much better than our LS CNP setup...
Thread Starter
On The Tree
Joined: May 2012
Posts: 160
Likes: 0
From: Port St. Lucie, FL
I see. These are brand new plugs and wires, replacing the stock ones. Hmm....well I went to Autozone and they hooked up the scanner tool and when the car was on and at idle, a certain value was fluctuating. I believe it had something Ignition related, I didn't look but he recommended to look into the Crank Position Sensor.
I know it's Autozone so I will take it with a grain of salt lol. This weekend my friend is bringing his Laptop with HP Tuner on it so we will figure out exactly what the hell is going on inside this LS1. It just makes me uneasy driving it with a SES light on, especially something misfire related. She's going to be sitting in driveway until I can get it looked at again, just in case.
I know it's Autozone so I will take it with a grain of salt lol. This weekend my friend is bringing his Laptop with HP Tuner on it so we will figure out exactly what the hell is going on inside this LS1. It just makes me uneasy driving it with a SES light on, especially something misfire related. She's going to be sitting in driveway until I can get it looked at again, just in case.
