Misfires BM3 Stage 1

[tysilvaF82]

Jaizero

Noted, thank you will do. I’m running stock plugs and gap, I was told that they should be fine for a stage 1 tune by my mechanic but no longer using that mechanic going forward lol. I’m planning redoing spark plugs with NGK gapped correctly and coils very soon and going to flash back to stock until I replace them. I figure I can do a stock flash and throw some e85 in the gas and see if the ignition timing looks any better since stock plugs should be fine for the stock tune right?

[milafei63682]

hi guys
i have a dumb question
should I use ACN91 or the CS map if I don't have access to good fuel? because I think CS map is stage 0 so creates less power so maybe more suitable for bad fuel?

[Jaizero]

Originally Posted by milafei63682

hi guys
i have a dumb question
should I use ACN91 or the CS map if I don't have access to good fuel? because I think CS map is stage 0 so creates less power so maybe more suitable for bad fuel?

You should use the 91ACN map.

The CS map still expects you to have good quality 91/93.

[Jaizero]

Originally Posted by tysilvaF82

Jaizero

Noted, thank you will do. I’m running stock plugs and gap, I was told that they should be fine for a stage 1 tune by my mechanic but no longer using that mechanic going forward lol. I’m planning redoing spark plugs with NGK gapped correctly and coils very soon and going to flash back to stock until I replace them. I figure I can do a stock flash and throw some e85 in the gas and see if the ignition timing looks any better since stock plugs should be fine for the stock tune right?

Sorry I didn't see this. For some reason I wasn't getting notifications for a while.

Stock plugs are fine with a bit of E85 just don't use more than ~2 gallons to a full tank of 93, otherwise you risk pushing the fuel trims out too far causing a code.

Your plugs should be gapped to .022 on any BM3 OTS tune except for Flex Fuel. Then they should be gapped a bit tighter to .020-.021.

[blazer4495]

Originally Posted by tysilvaF82

Jaizero

Noted, thank you will do. IÂ’m running stock plugs and gap, I was told that they should be fine for a stage 1 tune by my mechanic but no longer using that mechanic going forward lol. IÂ’m planning redoing spark plugs with NGK gapped correctly and coils very soon and going to flash back to stock until I replace them. I figure I can do a stock flash and throw some e85 in the gas and see if the ignition timing looks any better since stock plugs should be fine for the stock tune right?

I was in the same boat as you. 2 gallons of E85 fixed the issue. I am running BM3 stage 1 93 tune. The car runs so much better!!!

[milafei63682]

Originally Posted by Jaizero

You should use the 91ACN map.

The CS map still expects you to have good quality 91/93.

Hi
I flashed the CS map before I wrote that question so I decided to do some logs
I notice misfires under low load cruising like around 1500- 2000 rpms, 11 misfires in total from 3 different cylinders during a 10mins full warm-up (from complete cold-start to a warmed-up duration)

And I also notice a knock in 3rd gear WOT acceleration at 3600rpm but the IAT is very high 115 degrees F (46 degrees C) because I was trying to get the BM3 app connected so I was idling too long.

Last night I had a 4th gear WOT IAT was good, 81 F(27 C) and no knocks detected.

I just replaced my 97506 spark plugs and coils 2000 miles ago.

consider the ambient temp was 68 F.

really hot IAT WOT log
https://www.bootmod3.net/log?id=6731...4eb346bbc1057c

normal IAT WOT log
https://www.bootmod3.net/log?id=6730...4eb346bbc0f68e

sorry I didn't post the 10mins warm up log which contains lots of misfires because I thought it was too long

[Jaizero]

Originally Posted by milafei63682

Hi
I flashed the CS map before I wrote that question so I decided to do some logs
I notice misfires under low load cruising like around 1500- 2000 rpms, 11 misfires in total from 3 different cylinders during a 10mins full warm-up (from complete cold-start to a warmed-up duration)

And I also notice a knock in 3rd gear WOT acceleration at 3600rpm but the IAT is very high 115 degrees F (46 degrees C) because I was trying to get the BM3 app connected so I was idling too long.

Last night I had a 4th gear WOT IAT was good, 81 F(27 C) and no knocks detected.

I just replaced my 97506 spark plugs and coils 2000 miles ago.

consider the ambient temp was 68 F.

really hot IAT WOT log
https://www.bootmod3.net/log?id=6731...4eb346bbc1057c

normal IAT WOT log
https://www.bootmod3.net/log?id=6730...4eb346bbc0f68e

sorry I didn't post the 10mins warm up log which contains lots of misfires because I thought it was too long

What gap on the plugs are you running?

Both logs look pretty good. Minimal timing corrections, load and boost on target.

Does it misfire once it's warmed up?

[Jaizero]

Originally Posted by milafei63682

Hi
I flashed the CS map before I wrote that question so I decided to do some logs
I notice misfires under low load cruising like around 1500- 2000 rpms, 11 misfires in total from 3 different cylinders during a 10mins full warm-up (from complete cold-start to a warmed-up duration)

And I also notice a knock in 3rd gear WOT acceleration at 3600rpm but the IAT is very high 115 degrees F (46 degrees C) because I was trying to get the BM3 app connected so I was idling too long.

Last night I had a 4th gear WOT IAT was good, 81 F(27 C) and no knocks detected.

I just replaced my 97506 spark plugs and coils 2000 miles ago.

consider the ambient temp was 68 F.

really hot IAT WOT log
https://www.bootmod3.net/log?id=6731...4eb346bbc1057c

normal IAT WOT log
https://www.bootmod3.net/log?id=6730...4eb346bbc0f68e

sorry I didn't post the 10mins warm up log which contains lots of misfires because I thought it was too long

You also need to add LPFP, RAM Load Act, LTFT bank 1 and 2 to your logs.

Please follow my earlier log post exactly.

[milafei63682]

Originally Posted by Jaizero

What gap on the plugs are you running?

Both logs look pretty good. Minimal timing corrections, load and boost on target.

Does it misfire once it's warmed up?

It's stock NGK 97506 gap I measured it to be around 0.03''

Yes I think misfire is constant and random whether cold or warm. normally occurs when I am cruising around.

[Jaizero]

Originally Posted by milafei63682

It's stock NGK 97506 gap I measured it to be around 0.03''

Yes I think misfire is constant and random whether cold or warm. normally occurs when I am cruising around.

That gap is WAYYYY too loose.

Regap to 0.022 right now.

No wonder it's misfiring.

[milafei63682]

Originally Posted by Jaizero

That gap is WAYYYY too loose.

Regap to 0.022 right now.

No wonder it's misfiring.

from my observation the misfires occur mostly when I let off my gas pedal and at gear changes.
I will regap them and hopefully it will be fixed.
thank you very much.

[milafei63682]

Originally Posted by Jaizero

That gap is WAYYYY too loose.

Regap to 0.022 right now.

No wonder it's misfiring.

or should I use the stock BMW spark plug instead? because I am running the CS tune which isn't as aggressive as stage 1 is, it only requests 18-19 psi of boost, and NGK 97506 is colder plug so it may have ignition issues in low rpms? I'm afraid that a closer gap will only exaggerate this issue?

However I am having a detonation under WOT at 3600 rpm so if the colder NGK plug does this the stock BMW plug should be worse under such condition I am so confused now.

[Jaizero]

Originally Posted by milafei63682

or should I use the stock BMW spark plug instead? because I am running the CS tune which isn't as aggressive as stage 1 is, it only requests 18-19 psi of boost, and NGK 97506 is colder plug so it may have ignition issues in low rpms? I'm afraid that a closer gap will only exaggerate this issue?

However I am having a detonation under WOT at 3600 rpm so if the colder NGK plug does this the stock BMW plug should be worse under such condition I am so confused now.

Stop overthinking it.

ALL BM3 OTS tunes require a 0.022 gap with recommended NGK 97506 plugs. You clearly have no idea what you are worried about. Regap, reset adaptations, and relog.

If you aren't going to do what I suggest, I will not keep trying to help you.

I run the same plugs with the same gap running 50% ethanol and have ZERO issues in low rpm.