Car Misfiring... Help please...

[RockSolidGST]

Without the use of a logger i will try to give as much data as possible...


Car misfires when under heavy load ( 60-80% throttle in 45th )


Or when i boost over 12-13psi , i was boosting to 15psi before this ( t25 ) For months fine

If i keep the boost under 12-13 it will go to redline without misfiring.
This is why i think its the coil pack
Most mods are in my modlist


I just replaced the Plugs with 8.5mm wires

And denso iridum Plugs

This problem was happening b4 i replaced them , I know think its possibly the coil pack or tranistor pack. Is there any way to use a process of elimitation to find out what is causing this problem. It first started happening when it was very cold out. I just dont want to buy a new coil pack , and have that no solve the problem and be out 180+ $$ ...


Any feedback/help would be greatly appreicated.. Thanks guys

 

[ddavisaf]

Try dropping a new set of NGK BPR 6ES plugs in. Make sure you gap them at .028".
You might also want to run a boost leak test.

 

[talonTSIDriver]

Same as ^^^^ I have had 3 DSM's that gave me that code and just put some nice NGK's in there and clear the code, and no more CEL.

 

[RockSolidGST]

I replaced them with the same plugs that were in it when i bought the car... it was working fine when i bought it ovb....


I mean the plugs were 12.99 a peice , i just dont want to go buy new plugs and have that not fix the problem

Any reason why these plugs wouldn't be working correctly?

Also any way to tell if the coil pack/tranistor pack is bad?

 

[95TalonOwner]

What plugs were originally in the car? NGK BPR6ES are the best for the 4g63 platform. Plus they only cost around 1.50 each or something like that. If you don't have NGK BPR6ES in your car now, go out and buy them, gap them to .028, and see if that fixes your problem.

 

[RockSolidGST]

Alright i will try that , im gunna try and return the denso's tell them it makes my car misfire and i want my money back


Thanks guys ill try that today see if it solves the problem

 

[RockSolidGST]

Thanks guy , Solved the problem , Car pulls very good and hard....


Im on a t25 , and since i added the downpipe its holding 16psi up till 6,700 , is this normal?


Spikes to 18/19


But thank you , All is well