Fuel injector failure on s55 ?? Your thoughts

[e85m4]

First of im running on full e85 on stock fuel system !!

First couple of pulls on Cary's base map car had lots of misfires in higher rpm (above 6000rpm) in bank 2 cylinder 4.

Sent the log and he fixed the issue... car was running nicely after !!

The next morning i get into my car and i pushed the start button and the car took like 4-5 seconds to fire which never happened before since i own the car !!

From that moment the misfires appeared back !! Cary tried multiple fueling adjustments and it was still there !!

He suggested me to replace my ignition coil... when to the dealer to grab one and made the change... misfires where still there !!

He suggested me to change my plugs to NGK and have them gapped to .018'' which i did the next day ... misfires are gone in the high rpm range BUT they have now moved to low to mid rpm (3000 to 5000rpm)

Played with my ethanol level and it didnt help at all so now he suggested me to replace my fuel injector on cylinder 4... ive never heard of failing injectors on the s55 before so i was skeptical but ended up ordering a brand new injector and i should have it replaced on tuesday !!

When im doing part throttle i dont have any misfires its only under 100% throttle on full load between 3000-5000rpm that i can feel 2-3 hesitation into my acceleration...

So did someone on here ever experienced this kind of issue? My car only ran good for 1 day since i have made the switch to e85 and im kinda regretting this decision for now it costed me hundreds of dollars and i still dont know whats causing those 2-3 misfires i feel on full throttle in 3rd gear and up !!

-MK

[Justin.AutoTalent]

Have you measured the E85 level from your local station? On really bad days the pump we have locally is comparable to E60.

[tom @ eas]

Ignition Coil & Injector failures are not uncommon, we've replaced some in a few occasions on heavily-tracked M4s. Haven't seen any issues on street driven vehicles.

[e85m4]

Originally Posted by Justin.AutoTalent

Have you measured the E85 level from your local station? On really bad days the pump we have locally is comparable to E60.

I do the mixture myself starting from full e99 !! I assume the tune would adjust itself if the level of ethanol would be a little more or little less than 85% right?

[Justin.AutoTalent]

Originally Posted by e85m4

I do the mixture myself starting from full e99 !! I assume the tune would adjust itself if the level of ethanol would be a little more or little less than 85% right?

The ECU does adapt to change.

It is probably just the injector, we've seen them fail here and there. It is not a rare issue

[Fast4d]

I think running 99% E would be a problem. there is no E sensor to allow ECU to adjust. unless it is adjusting base of fuel-air ration and knock sensor for timing.

it would mean having to inject a higher volume of fuel. did you inform Cary of this?

I changed to the flex fuel spark plugs before loading the first E85 tune. I was getting a miss one one or two cylinders. the coil harness/plug is very sensitive and MUST be carefully connected and a full connection to be double checked.

I do notice it requires a must longer crank during cold start. I am still in the testing/logging phase so I'll bring that up.

[CaryTheLabelGuy]

Injectors are electrical components and CAN and DO fail, just like I stated to you privately (while we have been working together on this issue).

I have done and continue to tune a TON of these S55 E85 Custom Tunes and injector failure is something that can happen, regardless of what fuel is being run as I’ve seen NO correlation between injector failures and fuel being used. They happen equally on gasoline based fuels as they do with alcohol based fuels (E85) - the difference being that ethanol tuning shows the injector’s deficiencies easier, due to how ethanol tuning works. It’s atill very rare, but it happens.

Like I also stated to you earlier, you have a consistent misfire on Bank 2 ONLY, which is cylinders 4-6. Bank 1 is running optimally and as expected. Usually a tuning issue (like improper HPFP pressure) will show multiple misfires, randomly on all cylinders (Bank 1 and 2).

The process of troubleshooting a misfire is fairly simple: The tune itself was checked and adjusted to rule out a fuel-system tuning issue (which would show misfires on both banks, btw) - this came back negative. Next up was a possible plug issue (most common issue) and the plugs were supposedly gapped correctly and replaced (I’m not physically there to verify they were gapped and installed properly). Following that, the consistent misfires on Bank 2 persisted, so then we wanted to rule-out a potential coil issue of which you only replaced 1 of 3 coils (remember bank 2 is cylinders 4-6, so is a total of 3 cylinders). You should move that new coil around between the other coils in cylinders 5 and 6 as well to rule the other coils out on those cylinders! If that comes back negative, the only other logical place to look at a failure/deficiency is the injectors.

[CaryTheLabelGuy]

Originally Posted by e85m4

I do the mixture myself starting from full e99 !! I assume the tune would adjust itself if the level of ethanol would be a little more or little less than 85% right?

So, this is news to me. Maybe I missed this somehow. You aren’t sure of your exact ethanol content and do your own mixing, am I understanding this properly?

[FriedPiston]

Spark plugs, coilpacks and injectors (somewhat rare) are all prone to premature failure, and specially so with full E85.

It may save you a lot of money if you run a diagnostics test on the injectors with ISTA, or find a shop that can do this for you.

You can also see if upgrading to these coilpacks help: https://www.ignitionprojectsusa.com/...sku-ip-a122609

Although, I'm willing to bet E99-100 is probably the source of all your misfires even if you're diluting the ethanol content yourself.

[e85m4]

Originally Posted by CaryTheLabelGuy

Injectors are electrical components and CAN and DO fail, just like I stated to you privately (while we have been working together on this issue).

I have done and continue to tune a TON of these S55 E85 Custom Tunes and injector failure is something that can happen, regardless of what fuel is being run as I’ve seen NO correlation between injector failures and fuel being used. They happen equally on gasoline based fuels as they do with alcohol based fuels (E85) - the difference being that ethanol tuning shows the injector’s deficiencies easier, due to how ethanol tuning works. It’s atill very rare, but it happens.

Like I also stated to you earlier, you have a consistent misfire on Bank 2 ONLY, which is cylinders 4-6. Bank 1 is running optimally and as expected. Usually a tuning issue (like improper HPFP pressure) will show multiple misfires, randomly on all cylinders (Bank 1 and 2).

The process of troubleshooting a misfire is fairly simple: The tune itself was checked and adjusted to rule out a fuel-system tuning issue (which would show misfires on both banks, btw) - this came back negative. Next up was a possible plug issue (most common issue) and the plugs were supposedly gapped correctly and replaced (I’m not physically there to verify they were gapped and installed properly). Following that, the consistent misfires on Bank 2 persisted, so then we wanted to rule-out a potential coil issue of which you only replaced 1 of 3 coils (remember bank 2 is cylinders 4-6, so is a total of 3 cylinders). You should move that new coil around between the other coils in cylinders 5 and 6 as well to rule the other coils out on those cylinders! If that comes back negative, the only other logical place to look at a failure/deficiency is the injectors.

yep everything that we have talked about privately has been addressed !! I put all my effort into that cylinder 4 because the timing value was always different on that cylinder only !! It would have been a huge badluck if all 3 coils from bank 2 would have failed at the same time And i hope its only 1 injector not all of them that are going crazy !!

I might go back to fuel pump if the issue isnt fix after the injector replacement !!

[e85m4]

Originally Posted by CaryTheLabelGuy

So, this is news to me. Maybe I missed this somehow. You aren’t sure of your exact ethanol content and do your own mixing, am I understanding this properly?

I thought you were aware of it e85 is no longer available here so i have to buy e99 ethanol and do my mixture myself.. drained the fuel system to 1g... added 12g of e99 and 2.5g of regular pump gas ...

[FriedPiston]

Originally Posted by e85m4

I thought you were aware of it e85 is no longer available here so i have to buy e99 ethanol and do my mixture myself.. drained the fuel system to 1g... added 12g of e99 and 2.5g of regular pump gas ...

The least you should do is test the ethanol content of your mixture:

http://www.fuel-it.com/ethanol-content-tester/

[CaryTheLabelGuy]

This appears to be an ethanol content mis-calculation, which has apparently shown a deficiency on one of the injectors on Bank 2 (4-6).

It should be noted to anybody reading that may be doing their own ethanol mixing, never fill your tank at any level other than on the 1 gallon reserve tank mark (the “——“ you see on the DTA calculator on your dash when you go past “0”). The fuel gauge is very inaccurate and just because it indicates a ½ tank doesn’t mean that there is actually that much fuel in the tank.

Also, be sure to add into your caluculations the fact that most pump gas is E10 (10% ethanol). In this case, the OP is using an E10 gasoline AND mixing it with E100.

Furthermore, the M3/M4 has a 15.9 gallon tank and I always recommend physically spot-checking actual ethanol content with an ethanol/gasohol tester (can be picked up from a amazon for like $12), so be sure to get all variables into the calculation and use a good ethanol calculator like “E85 Calculator” for iPhone (if you have Android, I'm sure there are tons of options in the Google Play store).

[e85m4]

I have decided to drain my gas tank and go back on pump gas to see if the misfires would still be there and around the same rpm...

The answer= YES

So its not related to the ethanol mixture !!

This car gonna drive me crazyyy

[FriedPiston]

You may need to be more specific.

Step 1. Drain fuel tank

Step 2. Fill up with pump gas

Step 3. Which BM3 OTS map did you flash back to??

[e85m4]

Originally Posted by nars3000

You may need to be more specific.

Step 1. Drain fuel tank

Step 2. Fill up with pump gas

Step 3. Which BM3 OTS map did you flash back to??

My custom stage 2 93oct tune that Cary made me !! Never had this issue with that pump gas tune so its something else not related to gas thats causing those stupid misfires

[FriedPiston]

It's probably best to work with Cary directly if you're absolutely positive this isn't happening with the BM3 OTS maps (e.g. re-flashing the BM3 OTS map to verify). He should be able to assist you quicker/better via e-mail as opposed to waiting for him to respond on here.

Things like this happen all the time with custom tuning. Expect for things to be a work in progress for a bit...

[MNoob]

Originally Posted by Fast4d

the coil harness/plug is very sensitive and MUST be carefully connected and a full connection to be double checked.

So I've learned

[jc05e46m3]

Bro, all of your exclamation points are giving me anxiety.

[whoop_ass]

ok
so try this, flash to stock and test.
see if you have any misfires

next step try OTS map and see if you have misfire

[guess2098]

Originally Posted by whoop_ass

ok
so try this, flash to stock and test.
see if you have any misfires

next step try OTS map and see if you have misfire

Best resolution of the day

[e85m4]

Originally Posted by whoop_ass

ok
so try this, flash to stock and test.
see if you have any misfires

next step try OTS map and see if you have misfire

Will try that option and report back later on today !!