[AdventureNoodle]

Does anybody else have this issue where if you free rev the car in comfort or TRACTION mode, the RPM returns to normal, but when you free rev in sport / sport+ / DSC off, it causes the idle to come down to like 500 and judder the car and then come back up to the normal idle range?

I am modified with a custom BM3 tune and can probably get it tuned out, but I wanted to see if anybody else (including stock M2 owners) had this problem.

[gsm2x3]

Mine does it from time to time. Feels VERY mild. (No tune) I think I've seen it discussed somewhere before.

I could be mistaken but I wouldn't sweat it too much

[AdventureNoodle]

Originally Posted by gsm2x3

Mine does it from time to time. Feels VERY mild. (No tune) I think I've seen it discussed somewhere before.

I could be mistaken but I wouldn't sweat it too much

I wouldn't be annoyed with it as much if it didn't randomly do the judder at stop lights and stuff too (almost on a whim, I can never predict it). I have 0 clue what could be causing it apart from some specific throttle / timing settings on S/S+/DSC off.

Thankfully the car has never stalled on me.

I guess I'm extra vigilant cause I have modifications like a Dorch Stage 2 and am currently running high ethanol content.

[shaneguags]

I as well have this issue. could be spark plug or injector related

[AdventureNoodle]

Originally Posted by shaneguags

I as well have this issue. could be spark plug or injector related

I replaced my injectors with nostrum stage 1, plugs, and now I no longer have the problem. Seems like the plugs were gapped incorrectly too for the ethanol content I was running.

[shaneguags]

Originally Posted by AdventureNoodle

I replaced my injectors with nostrum stage 1, plugs, and now I no longer have the problem. Seems like the plugs were gapped incorrectly too for the ethanol content I was running.

how are those injectors by the way ? I literally just posted a forum asking about them also, what are you gapped at ?

[AdventureNoodle]

Originally Posted by shaneguags

how are those injectors by the way ? I literally just posted a forum asking about them also, what are you gapped at ?

So far so good! I'm getting my car back today with a pure stage 2 so hopefully it can flow enough fuel. My plugs are gapped at 0.020"

[shaneguags]

Originally Posted by AdventureNoodle

So far so good! I'm getting my car back today with a pure stage 2 so hopefully it can flow enough fuel. My plugs are gapped at 0.020"

okay cool, I just had NGK 97506 plugs gapped to .020 as well so I'm assuming it's the injectors like they were staying. have you noticed any significant change in performance with the Nostrum injectors ?

[AdventureNoodle]

Originally Posted by shaneguags

okay cool, I just had NGK 97506 plugs gapped to .020 as well so I'm assuming it's the injectors like they were staying. have you noticed any significant change in performance with the Nostrum injectors ?

Originally Posted by shaneguags

okay cool, I just had NGK 97506 plugs gapped to .020 as well so I'm assuming it's the injectors like they were staying. have you noticed any significant change in performance with the Nostrum injectors ?

Honestly yeah it's probably injector related.

I haven't pushed enough power to really even push these injectors hard tbh. I'll really know if they're good if it can handle full E85 at WOT at max boost. I'd the fuel pumps don't give out, the next weakest link are the injectors, and if those can keep up with the flow I'm demanding then I know they're good

[shaneguags]

Originally Posted by AdventureNoodle

Honestly yeah it's probably injector related.

I haven't pushed enough power to really even push these injectors hard tbh. I'll really know if they're good if it can handle full E85 at WOT at max boost. I'd the fuel pumps don't give out, the next weakest link are the injectors, and if those can keep up with the flow I'm demanding then I know they're good

yea see I was thinking about adding ethanol later but not sure if I wanna yet. I am big turbo and have a stage 2 hpfp so I'm not worried about the pump failing. only issue I been having is rough idle on cold start only was misfires in cylinders 1,2,4,5. I had spark plugs just done yesterday, coil ignitions done 2k miles ago, and never changed out the injectors so I'm assuming it's them. it's just weird though because my car only has 17,900 miles but I do know the previous owner used ethanol due to leaving the flex fuel lining kit on the car

[AdventureNoodle]

Originally Posted by shaneguags

yea see I was thinking about adding ethanol later but not sure if I wanna yet. I am big turbo and have a stage 2 hpfp so I'm not worried about the pump failing. only issue I been having is rough idle on cold start only was misfires in cylinders 1,2,4,5. I had spark plugs just done yesterday, coil ignitions done 2k miles ago, and never changed out the injectors so I'm assuming it's them. it's just weird though because my car only has 17,900 miles but I do know the previous owner used ethanol due to leaving the flex fuel lining kit on the car

Originally Posted by shaneguags

okay cool, I just had NGK 97506 plugs gapped to .020 as well so I'm assuming it's the injectors like they were staying. have you noticed any significant change in performance with the Nostrum injectors ?

Yup there's a solid chance it's injector related then. Misfires at low RPM are usually almost always injector related, especially if Ethanol was involved. Are you tuned on Bootmod3?

[shaneguags]

Originally Posted by AdventureNoodle

Yup there's a solid chance it's injector related then. Misfires at low RPM are usually almost always injector related, especially if Ethanol was involved. Are you tuned on Bootmod3?

yea I figured since I changed everything else and correct, I'm running stage 2 bootmod3. I have a custom file by my local tuner in CT

[AdventureNoodle]

Originally Posted by shaneguags

yea I figured since I changed everything else and correct, I'm running stage 2 bootmod3. I have a custom file by my local tuner in CT

What you could also do potentially is adjust your burble settings to not do anything below 1750 RPM. I noticed the biggest improvement after doing that.

[shaneguags]

Originally Posted by AdventureNoodle

What you could also do potentially is adjust your burble settings to not do anything below 1750 RPM. I noticed the biggest improvement after doing that.

oh really ? interesting I have mine set to 1100-8110. this helps with cold starts tho ?