Just got the car back from getting a clutch put in and before i put it in the shop it wasn't misfiring, but now it is. I thought it was the spark plugs, so i bought some new ones (NGK BPR7ES gapped to .026) and its still misfiring under load (normally around 3-4th gear at 5k rpms). Havent been able to do any logs as my tactrix cable has broken (come apart at the red connector) and the plug wires seem fine. I think they are gapped to far apart, but thats what i read here on the forums to be the correct gap. Only running 20-21 psi. Any help would be appreciated!

 

Interesting that it only happens under load... was the clutch install done at Mitsu? Any reason to believe they may have tapped or reflashed the ECU ?

 

Had that happen to me after a more aggressive tune and it ended up being the plugs being old and unable to cope with the added stress. Check those plugs and i bet the problem disappears.

 

.026 is the correct gap. how old are your plug wires?

 

The spark plugs are new and the wires im not sure how old they are. The car has 50k on it and i believe they are the original wires. The clutch job was not done by Mitsu, so i know they didnt touch the ECU. Im gonna go out now and regap the plugs down to .024 and see if that helps as well as check the UICP and DV for any leaks.

 

definitely gap .22/.24

tactrix cable, just solder it back together....

 

Thats what i thought i normally gapped the plugs too, but wasnt sure.

 

Regapped the plugs down to .024 and it fixed the problem. Thanks for the help guys!