Stupid Misfire

[slime_bullet]

Hello everyone, first post here.Bought a 2015 Mustang GT AT premium stock with 46k back in June of this year. Absolute mint condition as i was driven by a older woman in her 60's. However im trying to track down a little misfire, or may get verification that its ok. I didnt check this data prior to putting the mods on, so i dont know if existed when i purchase the car or my mods caused this. anyways heres my mods
FORD PERFORMANCE POWER PACK STAGE 2
ROUSH AXLE BACK EXHAUST PAIRED WITH STEEDA H PIPE
CHANGED SPARK PLUGS TO NGK RUTHENIUM GAPPED TO 0.052
Didnt like those plugs so i went back with new SP548'S
Also upgraded the coil packs to the MSD STREET FIRE COILS.
Problem, i accumulate random individual misfires on my mode 6 data on cylinders, but usually not at the same time, as they come in increments of 1. These are almost aways happening when im feathering on and off the throttle in bumper to bumper traffic, or increasing throttle from a coast. No misfires with cruise on or WOT.
Ive checked everything i could, even reinstalled the stage 2 kit. STFT and LTFT are spot on, vacuum looks to hold in gauge mode, all exhaust fitting are tighten to spec. no check engine lights, no stored codes, no pending codes. I dont really feel these misfires, they just show up in forscan and torque pro.
The only driveablitiy issue i have is taking off under light throttle and when it goes into second theres a little hesitation, but im thinking that might be the torque converter. Any ideas before i take her in? No warranty

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[ugstang17]

Go back to the stock Coil Packs. They are better. People are running them on 1000 HP setups. The MSD's are not reliable.

First rule of thumb. Always scan for codes after a drive before performing mods. Why people don't do this is beyond me. It's provides you a standard that you can compare to after you do the mods. Then and only then will you know soundly if mods or work related to mods created a problem.

So first rule would be to put the car back the way it was. Clear the codes. Drive it and then check for codes. Only way you will know if the problem was existent before hand.

And again. The MSD COP's will gain you absolutely nothing. The hype is simply that...hype. You can't beat the factory COP's.

 

[slime_bullet]

Go back to the stock Coil Packs. They are better. People are running them on 1000 HP setups. The MSD's are not reliable.

First rule of thumb. Always scan for codes after a drive before performing mods. Why people don't do this is beyond me. It's provides you a standard that you can compare to after you do the mods. Then and only then will you know soundly if mods or work related to mods created a problem.

So first rule would be to put the car back the way it was. Clear the codes. Drive it and then check for codes. Only way you will know if the problem was existent before hand.

And again. The MSD COP's will gain you absolutely nothing. The hype is simply that...hype. You can't beat the factory COP's.

Thank you for the reply. Can confirm the misfire to be there with the factory COP's also, but again this is after installing the ford performance pack 2. I had changed the plugs and ran with the factory cop's while the new cop's came in. I had scanned for codes before installing anything, i just didn't monitor individual cylinder misfires. Not throwing any codes. Ill take the ford performance pack off and see if its within those components, but the axle back and h pipe are pretty permanent.

 

[steveo1960]

Thank you for the reply. Can confirm the misfire to be there with the factory COP's also, but again this is after installing the ford performance pack 2. I had changed the plugs and ran with the factory cop's while the new cop's came in. I had scanned for codes before installing anything, i just didn't monitor individual cylinder misfires. Not throwing any codes. Ill take the ford performance pack off and see if its within those components, but the axle back and h pipe are pretty permanent.

When I had a similar situation, misfire w/no codes on my 2003 I ended up data logging through the SCT tuner connected to a laptop (stock tune and COP in car) and found the 2 sick COP right away by looking at the misfire data graph. Replaced them, with stock models and it's been fine ever since. Maybe you have access to something similar?

 

[slime_bullet]

When I had a similar situation, misfire w/no codes on my 2003 I ended up data logging through the SCT tuner connected to a laptop (stock tune and COP in car) and found the 2 sick COP right away by looking at the misfire data graph. Replaced them, with stock models and it's been fine ever since. Maybe you have access to something similar?

I actually have an sct tuner and laptop with livewire that i use for my 2012 f150. Can you explain what pid's i am looking for? ive attached an excel file of what i am seeing in forscan

 

[usgiorgi]

Check for any codes. Mine was sort of acting like this with no CEL. After a few days, a CEL popped up with a P0300 and a P0308. Turned out that my intake manifold runner control valves were cracked. Pretty common issue.

 

[slime_bullet]

Check for any codes. Mine was sort of acting like this with no CEL. After a few days, a CEL popped up with a P0300 and a P0308. Turned out that my intake manifold runner control valves were cracked. Pretty common issue.

thank you sir. checked for codes and all clear. its not a consistent misfire where you feel it and theres power loss, its 1 misfire at a time, over the coarse of my drive cycle. Definitely looked into the issue you mentioned, and it very well may be it, just hasnt gone full blown yet

 

[ugstang17]

Thank you for the reply. Can confirm the misfire to be there with the factory COP's also, but again this is after installing the ford performance pack 2. I had changed the plugs and ran with the factory cop's while the new cop's came in. I had scanned for codes before installing anything, i just didn't monitor individual cylinder misfires. Not throwing any codes. Ill take the ford performance pack off and see if its within those components, but the axle back and h pipe are pretty permanent.

The exhaust mods you installed have little/no effect. They are purely for sound. Further they would not generate any codes or issues with the stock tune. Hopefully someone with a PP aftermarket packages can chime in and give you some 411. I am running FI so plastic intakes and IMRC plates are not in my theory of troubleshooting. If your vacuum is good as you indicate then you may wish to look to see if the IMRC plates are sticking, binding, etc. I saw in this thread reference to those having issues. If vacuum is good and you have no LTFT1,2 issues (1.00) then you should also be good on vacuum. Often times a vacuum issue can be confirmed with low vacuum readings at idle by observing the LTFT's. If you are seeing large rich corrections in the LTFT's at idle to correct for AFR, and then they drop back to normal this is an indication of a potential vacuum leak. I am attaching the Ford tech manual on LTFT's for you to review. Its from an 11 manual but its still a Coyote engine and standard rules still apply.
http://iihs.net/fsm/?d=8&f=Adaptive Fuel DTC Diagnostic Techniques.pdf&p=1

 

[ugstang17]

I actually have an sct tuner and laptop with livewire that i use for my 2012 f150. Can you explain what pid's i am looking for? ive attached an excel file of what i am seeing in forscan

You will need to update the livelink and the SCt device possibly to get proper datalogging for all PIDS on your car. I tried using my X3 for a friends Pickup just to datalog and ended up bricking the software on the laptop. THe only way I was able to get livelink to work again with the SCT device was to restore the harddrive on the laptop and then load the revision of livelink I was using for my 2014. Don't know if it had to do with being married to my car or not, because I had bought that unit simply to datalog on my previous 2013 and used it unmarried with no issues. I spent hte whole day at his house trying to make the laptop sync with the SCT device. But after I it failed to sync to collect data on his truck it would no longer work on my car either until I restored the hard drive and reloaded Livelink. Could have been a laptop glitch but that would have been extremely coincidental.

As for PIDS you can scroll down and look for them in the screen after you validate PIDs to the vehicle if you try this. You will also want to monitor LTFT1,2 and STFT 1,2 as well as RPM, and your misfire pids. There may even be IMRC pids as well so monitor those also if they are there. Doing this on the laptop and saving the configuration is sooooo much easier than trying to create the config, convert it and export it to the hand held unit which is a waste of time in my book.

Best of luck

 

[slime_bullet]

The exhaust mods you installed have little/no effect. They are purely for sound. Further they would not generate any codes or issues with the stock tune. Hopefully someone with a PP aftermarket packages can chime in and give you some 411. I am running FI so plastic intakes and IMRC plates are not in my theory of troubleshooting. If your vacuum is good as you indicate then you may wish to look to see if the IMRC plates are sticking, binding, etc. I saw in this thread reference to those having issues. If vacuum is good and you have no LTFT1,2 issues (1.00) then you should also be good on vacuum. Often times a vacuum issue can be confirmed with low vacuum readings at idle by observing the LTFT's. If you are seeing large rich corrections in the LTFT's at idle to correct for AFR, and then they drop back to normal this is an indication of a potential vacuum leak. I am attaching the Ford tech manual on LTFT's for you to review. Its from an 11 manual but its still a Coyote engine and standard rules still apply.
http://iihs.net/fsm/?d=8&f=Adaptive Fuel DTC Diagnostic Techniques.pdf&p=1

Yes sir fuel trims have been checked at idle, 1500, and 2500 rpms. all well within normal range. my short term trim is 0-0.78, and long terms no great than 3 on both banks.
Did a crank shaft relearn multiple times also. Like you said, unless someone with the ford power pack 2 can chime in, im going to have to reverse the install and return to stock and see if it still happens. Or wait until i throw a code lol
car runs absolutely fine, you wont know there was a misfire unless you look at the individual cylinder misfires

 

[slime_bullet]

You will need to update the livelink and the SCt device possibly to get proper datalogging for all PIDS on your car. I tried using my X3 for a friends Pickup just to datalog and ended up bricking the software on the laptop. THe only way I was able to get livelink to work again with the SCT device was to restore the harddrive on the laptop and then load the revision of livelink I was using for my 2014. Don't know if it had to do with being married to my car or not, because I had bought that unit simply to datalog on my previous 2013 and used it unmarried with no issues. I spent hte whole day at his house trying to make the laptop sync with the SCT device. But after I it failed to sync to collect data on his truck it would no longer work on my car either until I restored the hard drive and reloaded Livelink. Could have been a laptop glitch but that would have been extremely coincidental.

As for PIDS you can scroll down and look for them in the screen after you validate PIDs to the vehicle if you try this. You will also want to monitor LTFT1,2 and STFT 1,2 as well as RPM, and your misfire pids. There may even be IMRC pids as well so monitor those also if they are there. Doing this on the laptop and saving the configuration is sooooo much easier than trying to create the config, convert it and export it to the hand held unit which is a waste of time in my book.

Best of luck

got it, was able to connect with no problem and validate pids

 

[Cobra Jet]

Go back to the stock Coil Packs. They are better. People are running them on 1000 HP setups. The MSD's are not reliable.

...

And again. The MSD COP's will gain you absolutely nothing. The hype is simply that...hype. You can't beat the factory COP's.

Sound advice...

Just had to at that MSD comment... brings back memories because their COP’s and 79-2004 Mustang coils were garbage, just as were the old school MSD ignition boxes... there’s not a forum online that doesn't have at least 1 thread about an ‘XYZ’ MSD failure...

 

[steveo1960]

I actually have an sct tuner and laptop with livewire that i use for my 2012 f150. Can you explain what pid's i am looking for? ive attached an excel file of what i am seeing in forscan

Sorry for delay in replying. So I performed this like 8 years ago with an SCT 2 tuner and the current version at the time of LiveWire. As I recall, I just selected something like "Spark and Ignition" from the list of events to data-log. So when I displayed the results, most of the cylinders had counts under 10 (about a 5 minute data log) except for 2 cylinders which had misfire counts in the hundreds. So unlike your data log, it was very obvious with my car which cylinders had the problem. I replaced those 2 COP with new ones (Ford), data logged again, and this time all misfire counts were in single digits, approximately, and the intermittent hesitation due to misfire was gone.

One thing about my car, when this first started, it was much, much worse on rainy days which makes sense since both the defective COP had hairline cracks in them. I also had no codes stored. Just a very intermittent hesitation.

 

[slime_bullet]

Sorry for delay in replying. So I performed this like 8 years ago with an SCT 2 tuner and the current version at the time of LiveWire. As I recall, I just selected something like "Spark and Ignition" from the list of events to data-log. So when I displayed the results, most of the cylinders had counts under 10 (about a 5 minute data log) except for 2 cylinders which had misfire counts in the hundreds. So unlike your data log, it was very obvious with my car which cylinders had the problem. I replaced those 2 COP with new ones (Ford), data logged again, and this time all misfire counts were in single digits, approximately, and the intermittent hesitation due to misfire was gone.

One thing about my car, when this first started, it was much, much worse on rainy days which makes sense since both the defective COP had hairline cracks in them. I also had no codes stored. Just a very intermittent hesitation.

Thank you for sharing. Not getting anything in the hundreds, just single digits on a 15 mile commute with a lot of bumper to bumper traffic. Probably close to 40 minute drives. No hesitation or anything like that. And it seems to happen under 1500 rpms when very lightly accelerating the letting go of the throttle. Theres no rhyme or reason to it. Some days its one cylinder with the most, then next drive cycle there are no misfires on that cylinder. I do notice it happens less while running the heater or air conditioner. Maybe its just an over sensitive crankshaft sensor

 

[Rooster66]

Been reading these posts about ignition coil packs. My latest nightmare of wasted loot is with MSD street fires on a Gen 2 Coyote. These packs lasted 4 months of summer daily driving. OEM packs are absolutely essential if you want a healthy ride and non-problematic. MSD, Accel and all other aftermarket coil packs will not hold up as long or as good as the packs designed and made in USA. MSD are made in Mexico and if anyone thinks they take pride in preserving quality they are wrong. Accel packs I've had problems with also. Listen to experience....It's the most valuable tool..!!!!

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