Misfire/backfire

[FiveLeeter918]

Gentlemen, I have the standard SHO with a Diablo tuner. I run the 93 tune. I did nothing else to the car. Put it in new at 4k miles. She has 126k on it now. She just started with the misfire getting on the freeway. I took the tune out and the problem went away. Put it back in and its back. So, from this thread, I am hearing spark plug change. This is my daily driver and work car. (outside sales it a 2016). The stock stuff worked before, any reason not to use it again?
Thanks
Rick

Definitely start with plugs, it sounds like the Diablo tune is commanding more than the old spark plugs can withstand. Get a set of SP542s, gap to 0.026", and drop them in.

My assumption is you've never datalogged the Diablotune, are you running a 5 star canned tune or just the tune from the handheld itself?

 

[Rick Steinard]

First things first, change the plugs and throw the Diablo tuner in the trash. Get a proper tuner and tune, and your car will run a lot better.

Hmm, not that helpful. Please define "proper tuner". What I have has worked fine for over 120,000 miles. A simple "yes change the plugs" would have been sufficient.

 

[Rick Steinard]

Definitely start with plugs, it sounds like the Diablo tune is commanding more than the old spark plugs can withstand. Get a set of SP542s, gap to 0.026", and drop them in.

My assumption is you've never datalogged the Diablotune, are you running a 5 star canned tune or just the tune from the handheld itself?

Just a off the shelf T1000. No complaints, works fine for my daily driver/ work car.
Is SP a brand of plug?
Thanks
Rick

 

[SM105K]

Hmm, not that helpful. Please define "proper tuner". What I have has worked fine for over 120,000 miles. A simple "yes change the plugs" would have been sufficient.

A proper tuner and tune is what I said. If you are using a canned tuned for this platform you are leaving performance, mileage, and in some cases reliability to chance.

If your canned tune is amazing, "yes change the plugs" is sufficient.

If you want to learn, possibly have a better driving experience, and enjoy your 16 more, then being a little more receptive may help. There is a ton of knowledge on this board, and the consensus is, canned tunes are trash.

Ortiz, Gearhead, AJP, can write a custom tune for your car that will outperform your canned tune in their respective sleep.

 

[FiveLeeter918]

Just a off the shelf T1000. No complaints, works fine for my daily driver/ work car.
Is SP a brand of plug?
Thanks
Rick

SP542s are oem for the F-150 Ecoboost, they are Motorcraft brand.

 

[FiveLeeter918]

Hmm, not that helpful. Please define "proper tuner". What I have has worked fine for over 120,000 miles. A simple "yes change the plugs" would have been sufficient.

I have to tend to agree with SM105K, it's not that the Diablosport itself is a bad system, it used to be the top tier performance programmer, but it's just old technology that was never updated with the times and carries with it very limited support. Few tuners still mess with it, so the expertise of the tune is lacking and with that so is the ability to datalog issues.

Were you SCT tuned, you could easily datalog parameters to tell exactly what the issue is rather than guessing and changing out parts to hopefully see a positive result.

Just my 2 cents, here to help.