Hi. For quite a while I thought my car was getting fuel cut from overboosting in 5th but someone has told me fuel cut feels like hitting a brick wall where what I'm getting is a little stutter, so now I'm thinking it might be a missfire. I fitted a COP kit a while back which made no difference but someone else has told me that they had the same problem in their car and changing the type of plug they were using sorted it. I was just wondering what plugs people are using in their IX's? I'm 400hp at the fly, basic bolt-ons. I put some new ilfr7h's in there not long ago but it still misses in 5th sometimes at WOT.

Any ideas appreciated

 

Check your gap!!

 

400hp at the flywheel is not much and you shouldn't need a COP.

I would say to check plug gaps as suggested and then check your tune.

Any reason you are doing 5th gear pulls? I assume this is after revving out 4th? 5th in a lower rpm is a huge load which can cause a number of issues and usually should not be performed. Even more so on a stock block.

 

Hi. The plugs are still at the standard gap, not quite .5mm I think. If anyone has got some tips on how to widen a iridium plug or a link to a decent tool for it that won't apply pressure to the tip I'd happily try and widen the gap. No I'm not doing 5th gear pulls, I'll rip through the gears as normal but the miss only seems to happen in 5th.

Thanks

 

NGK ILFR7H gapped at .020" (whatever that translates to in mm, .51mm or something)

 

Just use some needle nose pliers to open the ground electrode. Then check with a feeler gauge carefully. Don't use one of those tapered coins.

Are you logging during the pulls? That would assist in troubleshooting as well.

 

It is already gapped to .5mm or there abouts. .6mm doesn't fit. No data logging unfortunately. I did have a go with needle nose pliers a while ago but couldn't get in between the tip and the ground electrode and couldn't see any other way of prying it really. Maybe I'll have another go and see if I can come up with a good way of adjusting it

 

grip and pull from the sides, dont pry from between the tip and the ground electrode

 

OK cool, I'll have a go this weekend. Will I feel it move or shall I just keep giving it little tugs and then check the gap again?

 

Probably won't be able to tell. Just give it some pressure and recheck until OK.