[LLCoolJ94]

I know there is another post concerning this, however I have a little different of a problem.

My rpm jump around at idle. Not like I have a vacuum hose leak, but say 50-100 rpm, and the idle is rough, plus it misses constantly. I have switched out the plugs to NGK 6097 gapped at 0.030 and only have 10k on a new motor. I am pretty sure that the coil packs are brand new as well, 10k old with the engine. I have a S-AFC tuned and I don't know what the problem is.

Joe

 

[devioust78supra]

Rough idle is typical when you gap the plugs down. Try a stock raising your gap if your car is having a problem.

-Chris

 

[LLCoolJ94]

WTF? I am BPU, why would I run stock plugs and go with a 0.036 gap? I think you need to read www.mkiv.com about spark plugs then get back to me.

Anybody else?

Joe

 

[99YellowStang]

WTF? I am BPU, why would I run stock plugs and go with a 0.036 gap? I think you need to read www.mkiv.com about spark plugs then get back to me.

Anybody else?

Joe

the guy is just trying to help, dont be an ass

and your idle isnt really rough, make sure ur coil packs are new if you think its missfiring

 

[supra400hptt]

I just did a search on idle last night and came up with 12 pages. Try looking again. It's been asked over and over.

 

[LLCoolJ94]

Krystian, I'm not trying to be an ass.

I did a search, most of the answers were plugs, coil packs, etc. I switched out the plugs and immediately, the missing continued, not nearly as bad as before I switched them. Larry said my coil pack were new, hence, I am asking this question. I said I wasn't sure that they are brand new because I haven't tested them by switching them out, I don't want to make a $40+ investment in something that I may not need.

Any other ideas?

 

[devioust78supra]

I won't be a D*CK and respond as ignorant as you did so I'll try to help out instead.
1. Check your S-AFC wiring and make sure they are all properly correctly connected to the ECU and clean connected to all wires.

2. Double check all of your hoses that you suspect may have a tear.

3. Try raising the gap to either STOCK gap and see if this eliminates the issue.

4. I've been BPU+++ since 98 and haven't ran stock plugs but people have ran stock Denso plugs and gapped them down so I guess your comment was because you did not understand what I was trying to say, basically I was telling you to put your plugs back to stock gap and see if the problem persists, if it does you know it probably is not the plugs and you can then test your coil packs and go from there.

Lastly, do you have cam gears? Make sure the timing on your car is set correctly.

Next time, when someone tries to help you out, don't flame...that's the last thing you want to do. Good luck!

-Chris
97 T-78
594RWHP @ 19psi (pump/propane)
http://www.angelfire.com/ab/teamdevious

 

[LLCoolJ94]

The S-AFC wiring looked fine.

I did misunderstand what you meant, I appologize for that.

I will try to regap the plugs.

I do not have cam gears.

Joe

 

[devioust78supra]

If gapping the plugs does not help then I suggest checking your MAF connections (swap a MAF if possible) and make sure all your other components are fine in terms of your motor, fuel, ignition, ECU...list goes on.
Easisest way to start is by raising your gap to troubleshoot.
However, with your plugs gapped down, don't expect your idle to be as it was with a stock plug gap, it will always bounce around 100 to 200rpm. Another solution is to raise your idle if this is of great concern.


-Chris