Hi guys

Have a GP2 at around 6000 miles now

The car has been developing misfire under high load, 4th gear 4000 rpm or whenever the car is at full throttle more than a few seconds in high gear/high rpm.

Thinking that the coils are on the way out, i swapped in a set of Brisk QR12LS plugs and Ignition Projects coils.

After a full throttle highway pull, it misfired hard and ran rough. Swapped the stock plugs and coil again and it ran fine except it still misfires under high load/rpm.

Codes pulled are:
P0300 Random/multiple cylinder misfire
P0301 Cyl 1 misfire
P0304 Cyl 4 misfire
P0302 Cyl 2 misfire
B2AAA Body(?)

Mods on it are:

JB+
Miltek Decat downpipe
Forge Intercooler
Forge BOV
K&N Replacement
2.5" valved exhaust

Have looked for leaks and redid all piping with hairspray+alcohol trick to no avail.

Does this sound like a HPFP issue??power also seems to be much lower than before too.

 

You Might have to progressively take it back to stock to see what is doing it since you have a mix of mods.

That would be my first start, take off the tuners first and Forge BOV, if you are under warranty the dealership can see about the HPFP.

 

Watch those BOV's. These cars have fits.