Misfiring at WOT

[z4ck]

Hey guys, about a week ago my 1J went into limp mode, mifiring, not going over 20% throttle, and threw a code 14. I read that that was related to the ignitor so I disconnect and reconnect it and the car ran great... for about 1 day. After that it now stumbles at WOT, but the weird thing is I can get it to rev up alright at about half throttle. I've heard this can be related to cracks in the coil packs? My ECU had caps replaced about a month ago (had the same limp mode problem) and I already checked that, it seems to be fine, I also checked the spark plugs to see if they were fouled - they seem to be in good condition. I disconnected my battery yesterday to reset the ECU and the problem went away until this afternoon when it started happening again. Does anybody have an suggestions on what I should check first?

Thanks!

 

[hvyman]

What are your plugs gapped to?

 

[z4ck]

I didn't gap them, i'm just using pregapped BKR7E, I know that isn't ideal but they have been running fine so far... I will try that today.

 

[bioskyline]

are you stock or single on the jz? boost breakup on large single's are common..

 

[z4ck]

are you stock or single on the jz? boost breakup on large single's are common..

Still using the twins. I will try to take a video tomorrow so I can show you guys exactly what is happening. It still revs up but it misfires a shit load @ full throttle. I found a crack on one of the coil plugs and put jb weld on it plus regapped plugs to 0.025

 

[seoul4korea]

Still using the twins. I will try to take a video tomorrow so I can show you guys exactly what is happening. It still revs up but it misfires a shit load @ full throttle. I found a crack on one of the coil plugs and put jb weld on it plus regapped plugs to 0.025

Regap them to .028-.030 and get a hold of some shrink wrap for the coils. You might have to replace that coil though.

 

[z4ck]

Regap them to .028-.030 and get a hold of some shrink wrap for the coils. You might have to replace that coil though.

I was looking at heat shrink before I started this thread actually, but it's hard to find 1" locally. I found a store that has it though and will pick some up on Monday.

 

[seoul4korea]

I was looking at heat shrink before I started this thread actually, but it's hard to find 1" locally. I found a store that has it though and will pick some up on Monday.

If that doesn't work out I think home depot or lowes might have the right size.

 

[ATL88Supra]

this is not a gaping problem check the map sensor and other efi parts

 

[seoul4korea]

this is not a gaping problem check the map sensor and other efi parts

I think you're right as well, I just figured he should have them properly gapped as well since he said he was running .025 which would cause breaking up (But not limp mode)

 

[z4ck]

I think you're right as well, I just figured he should have them properly gapped as well since he said he was running .025 which would cause breaking up (But not limp mode)

They were at 0.028 but I put them down a bit. I will regap them back. Does anyone else think it is weird though that when I replugged in the ignitor the code 14 went away? I'm still waiting for the JB weld to dry completely and see if that fixes the problem.

 

[z4ck]

Good news everybody! Putting JB Weld on the cracked connector fixed the issue entirely. I will be getting some heat shrink for all of the coils so this never happens again on Monday. My car seems to like the 0.025 gap too so I will probably keep it there.

 

[seoul4korea]

Good news everybody! Putting JB Weld on the cracked connector fixed the issue entirely. I will be getting some heat shrink for all of the coils so this never happens again on Monday. My car seems to like the 0.025 gap too so I will probably keep it there.

Good news indeed!

 

[z4ck]

Good news indeed!

[video=youtube;1D1cap6yETA]http://www.youtube.com/watch?v=1D1cap6yETA[/video]