Persistent Idle Misfire

[Daryl333]

2017 6R80 Gen 3 Whipple.
Stage 2 closed airbox.
Anyone have an Idle Misfire and have done absolutely everything to find it with no success?
Or after trying everything you solved it with a rare fix? Car has NO CODES but shows Misfires at idle on all cylinders at varying times on different drive cycles.
After returning home parked in driveway Misfire is is increased x2 after a normal or somewhat spirited drive. Runs perfectly at WOT. Does have a rare hiccup sometimes between 2800-3500 RPM. But so rare I can't capture it in a log. Lund says logs are fine of course.
We have tried Smoke x3, Brake cleaner x3, Propane, Compression test_Passed.
NEW: Tune, Fuel System, Injectors tested, Plugs x2, MAF, Coils.
Reflashed and tried different tune.
Electrical Harnesses, fittings eyeballed checked for anomalies etc.
MAF/TB cleaned. I am going to install a Fuel Line Damper next week hoping...
I've found what others have tried etc but have seen a couple out there like mine that still haven't found a solution. Still others have said due to large 132 TB and 1050 injectors are what causes it and to forget about it. I don't agree. I can live with and have for months but don't like it.
Any ideas/options?
Thx.

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[Pistol_91]

I would say pull the plugs and check them or check the coils but looks like you already threw the book at it. Only does it at idle? If others seem to think its the large TB I would try a smaller sized one and see how it performs with that if possible. Other than that, maybe try a different tuner.

 

[Torinate]

lol.

Hey Daryl. I’m watching this thread now too.

Praying for some good advice and solutions bud!!

 

[Daryl333]

I would say pull the plugs and check them or check the coils but looks like you already threw the book at it. Only does it at idle? If others seem to think its the large TB I would try a smaller sized one and see how it performs with that if possible. Other than that, maybe try a different tuner.

I've thought of changing out the TB but that would be an expensive and questionable option without issues poining at it. And it functions great otherwise.
And this is the second tuner with no change in Misfire.
But thx for the reply.
Any opinions are welcomed at this point.

 

[GregO]

Any ideas/options?

Spark plugs installed with threads lubricated or dry ?
Dielectric grease used anyplace ?

 

[Daryl333]

Spark plugs installed with threads lubricated or dry ?
Dielectric grease used anyplace ?

Dry no Grease.

 

[GregO]

Dry no Grease.

Whose plug, what number and air gap setting ?

Have you considered using GT500 coils ?

 

[Lonniesgt]

I have the gen 5 whipple stage 2 with 150mm throttle body and id 1050x inj. Same issue, lund tuned too. Had injectors cleaned, new plugs and coils too, do you have catless lth? I'm kinda thinking it's just nature of the beast. I couldn't find anything wrong with it. So I just figured we'd have to live with it.

 

[Torinate]

I have the gen 5 whipple stage 2 with 150mm throttle body and id 1050x inj. Same issue, lund tuned too. Had injectors cleaned, new plugs and coils too, do you have catless lth? I'm kinda thinking it's just nature of the beast. I couldn't find anything wrong with it. So I just figured we'd have to live with it.

I hear you.

EB 2650. Daryl and I have chatted about this ad nauseam. Same issue with the idle misfires. I also have a throttle hesitation when I stab the gas from idle. No idea if related or not. That is the biggest issue for me. Stab the gas. Wait for a second while the car sputters and then take off.

The idle misfires I can hear them pop at idle and watch Forscan add another misfire. No codes though. 2 different TBs. No luck. New plugs, injectors cleaned, smoke test x 3, cleaned MAF, changed catch can and eliminated it for trial, checked by pass valve. All with nothing. Talked to Lund but fell on deaf ears unfortunately. May try another tuner, but I’d hate to spend the money for no change. I do really wonder if the tip in is correct in the tune for the hesitation. I’d be happy with that fixed! How can I see this or check this? Can it be logged somehow to find a definitive answer one way or the other?

Daryl has similar issues all around lol.

Help one help all!!

What is the best way to log misfires though. I find it a pain to log with Forscan. nGauge won’t log them - at least I haven’t found it.

So, what’s everyone’s go to for logging them?

What plug gap is everyone running as well?

 

[GregO]

What plug gap is everyone running as well?

What plug brand, part number and gap are you using ?

 

[Daryl333]

Who’s plug, what number and air gap setting ?

Have you considered using GT500 coils ?

NGK6510
Have tried .028" and .026". Have thought of bumping it up to .030" just to see but haven't yet.
No never thought of using those Coils.
I bought brand new OEM Coils.
I mean they work for thousands of others right?

 

[Daryl333]

I have the gen 5 whipple stage 2 with 150mm throttle body and id 1050x inj. Same issue, lund tuned too. Had injectors cleaned, new plugs and coils too, do you have catless lth? I'm kinda thinking it's just nature of the beast. I couldn't find anything wrong with it. So I just figured we'd have to live with it.

I had Catted ARH Longtubes.
Lund thought that it might be the Cats getting clogged so I instead of dicking around removed the Headers and went with an OEM set of exhaust with about 80 miles on them.
No change.
Yes have been told by non Mustang owners it's the nature of the beast. If it was then why don't thousands of others with this set up have idle misfires? Right.
I also have hiccup when tipping in at around 2800-3500 that is the worst problem tho.
Hoping the fuel Dampener helps.

 

[GregO]

NGK6510
Have tried .028" and .026". Have thought of bumping it up to .030" just to see but haven't yet.
No never thought of using those Coils.
I bought brand new OEM Coils.
I mean they work for thousands of others right?

Couple of things to think over.
The NGK 9510 is factory gapped @ .043, bending the grounding electrode to say .022~.030ish isn't good practice. You'd be better off finding an NGK Iridium with a factory gap close to .030 and close that up. I think most SC plugs are set to .022~.026 range.
Makes a guy wonder about 5.0 coils when the new GT500 comes with 50 mJ coils. I think the highest mJ COP is around 80 mJ to put things into perspective.

 

[Daryl333]

Couple of things to think over.
The NGK 9510 is factory gapped @ .043, bending the grounding electrode to say .022~.030ish isn't good practice. You'd be better off finding an NGK Iridium with a factory gap close to .030 and close that up. I think most SC plugs are set to .022~.026 range.
Makes a guy wonder about 5.0 coils when the new GT500 comes with 50 mJ coils.

2 different top tuners have told me to use the NGK6510 plugs gapped at 26 or 28 for my 10-11 lbs boost.
I've tried 2 different sets or maybe 3 now. Lol
But it's worth a shot to try something else I guess.
On the Coil matter my set up is very simple 674/535 and guys with big boy power are still using OEM Coils.

 

[GregO]

2 different top tuners have told me to use the NGK6510 plugs gapped at 26 or 28 for my 10-11 lbs boost.
I've tried 2 different sets or maybe 3 now. Lol
But it's worth a shot to try something else I guess.
On the Coil matter my set up is very simple 674/535 and guys with big boy power are still using OEM Coils.

Take a look at the GT500 NGK plugs,
Platinum ground, factory gap set at .039

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