Rb25det Running ROUGH

[Rb25detJay]

Hey guys I have an rb25det swapped 240sx which i received recently.

I changed the following things recently

spark plugs from brp6es to brp7es
Coil packs from Yellow jackets to splitfires

I noticed it was backfiring on idle and when I revved it, it seemed to be revving rough or have some sort of lag.

I gapped the brp7es to .28 and the backfiring at idle stopped.

However, the rough idling and the rough shaking still stays, any ideas on what it could be ? Thanks


I'm relatively new to the S chasis and the RB, any and all help would be appreciated.

[S14rebuild]

1st post=1 reply......did u check timing?

[BenRice]

If it already had Yellow Jacket's in it then someone's encountered this issue before and tried to fix it.

When you swapped the plugs, what did the old ones look like? Black? White? Or all different?

Check the grounds for the coilpack harness - not just the connection, but the wire in the terminal might be cracked. Better yet, run fresh grounds from the coilpacks, even temporarily to check if that's the issue.

After that, throw a fresh fuel filter at it and double check the voltage at the fuel pump