Yes iv looked in the forums and stuff, but my p0300 problems kinda weird

when im on highway in 5th gear usually in between 70-80 mph, when i accel then deccel (not letting off the throttle) while im lightly on the throttle then i press down just a little and it starts to shudder and vibrate, more gas more vibration and the car just shakes and does not accel (feels like I started a chain of misfiring) then guess wat? throws a cel p0300. when at WOT theres no problem just when im lightly on the throttle. When it vibrates i let off the throttle and just give it throttle again and its just like nothing happened and a couple mins later it does it again....

i regapped the plugs and it didnt do anything except make my car worse, i cant even WOT without misfiring after i regapped.

then i just bought some ngk iridium plugs hoping it might possibly be bad plugs but that didnt do anything

seems to be that it misfires more in the rain and after a full tank of gas it seems like it likes to misfire. also after driving it on the freeway for 20+ mins

anyone have any idea?? thx

 

did you get your gas at the "normal" location?

 

sounds weird right lol and yes gas is normal i get gass usually at wawa and sunoco

 

What are you setting your gap at?

 

the ngk plugs i just put it in out the box, it looked a little lower then the stock plugs which i set at .04

 

i get the exact same thing, but i know why mine is doing it...it is because the clutch is emitting some harmonics through the drivetrain and setting off the knock sensor...

did you do any upgrades to your car before this happened?

 

OK I know what your problem is and I will tell you what's causing is and how to fix it (maybe)

first of all your guess that it is harmonics is correct, there are only four pickups on the crank position sensor and the harmonics confuse the the knock sensor and so the ecu cuts igniton and you get the misfire and 0300 code.

fixes
1. get ecu reflashed by dealer for factory fix (most likely won't work)
2. get creader off ebay for $45.00 (helps catch erant codes and fixes cell light when it comes on)

hope this helps

 

OR, you can do what i did and get an AEM EMS...

 

Do you mean .040? You should be gapping them at .025-.030. That is way to much of a gap. If that is the case gap them to .025 and see if that fixes your problem.

 

Harmonics... damn that sucks

well thnx guys i guess i look into it more

 

[QUOTE=SEEYA]i get the exact same thing, but i know why mine is doing it...it is because the clutch is emitting some harmonics through the drivetrain and setting off the knock sensor...

What clutch do you have?
Will the exedy twin clutch cause this problem?

 

Im having the EXACT same problem right now. I bought some new NGK spark plugs and maybe that'll fix it. If not, I dont know what to do.

 

^^^^^^^^^^^ +1