Bad direct injector?

[MOA90]

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[razorlab]

No need for that tight of gap.

 

[MOA90]

No need for that tight of gap.

I didn't realize, but I'm hoping for an easy fix! Thanks for all the help!

 

[razorlab]

I didn't realize, but I'm hoping for an easy fix! Thanks for all the help!

Just use OEM gap.

What do your LTFT and STFT look like?

 

[MOA90]

Just use OEM gap.

What do your LTFT and STFT look like?

I haven't looked at them myself but @Twisted Tuning has looked and hasn't said they are concerning.

 

[dismii]

Alright just to chime in on this post as im having same issues as posted before

ive changed all plugs using ngk standard gap a new set
one injector
two coils
changed intake manifold gasket seal on port injection plate
also had a leak down and compression check all passed with flying colors
misfire still occurs on start and idling,
also tried flashing back to stock didn't change anything
unplugged port injection and same thing
unplugged motive reflex and harness same thing
tried 4 diff tunes same thing

if anyone has any guidance let me know
i did see on gen 1 the cam shaft ledge tend to break on cylinder 1 my guess is probably what I'm experiencing

 

[MOA90]

Alright just to chime in on this post as im having same issues as posted before

ive changed all plugs using ngk standard gap a new set
one injector
two coils
changed intake manifold gasket seal on port injection plate
also had a leak down and compression check all passed with flying colors
misfire still occurs on start and idling,
also tried flashing back to stock didn't change anything
unplugged port injection and same thing
unplugged motive reflex and harness same thing
tried 4 diff tunes same thing

if anyone has any guidance let me know
i did see on gen 1 the cam shaft ledge tend to break on cylinder 1 my guess is probably what I'm experiencing

Have you looked at your O2 sensors?

 

[Kujiwara]

May want to check Vanos function while checking camshaft

 

[dismii]

Have you looked at your O2 sensors?

yeah swapped and same thing sadly

 

[MOA90]

I tried to upload logs but .csv’s aren’t allowed. One thing that’s jumping out to me is my AFR goes sky high, as in the 100’s when I let off the throttle. I’m not sure what STFT and LTFT are supposed to be but mine sit in the -20’s for LTFT and range from -5 to +20 for STFT.

Also, I swapped the upstream O2 sensor (closest to turbo) off his Supra (his is running fine) to my car and it definitely improved the rough idle but wasn’t perfect. Not sure if I should swap both O2’s to test because I wasn’t sure if the downstream O2 would make a difference.

Any help is very much appreciated!

 

[razorlab]

I tried to upload logs but .csv’s aren’t allowed. One thing that’s jumping out to me is my AFR goes sky high, as in the 100’s when I let off the throttle. I’m not sure what STFT and LTFT are supposed to be but mine sit in the -20’s for LTFT and range from -5 to +20 for STFT.

Also, I swapped the upstream O2 sensor (closest to turbo) off his Supra (his is running fine) to my car and it definitely improved the rough idle but wasn’t perfect. Not sure if I should swap both O2’s to test because I wasn’t sure if the downstream O2 would make a difference.

Any help is very much appreciated!

Injectors shut off when throttle closes so normal for AFR to go full lean.

LTFT at -20 is maxed out at trying to reduce fuel, seems like something is dumping fuel in. Healthy car/tune should have LTFT at approx. +/- 1

 

[MOA90]

Injectors shut off when throttle closes so normal for AFR to go full lean.

LTFT at -20 is maxed out at trying to reduce fuel, seems like something is dumping fuel in. Healthy car/tune should have LTFT at approx. +/- 1

Thank you for the info! Any suggestions on things to look at? If something is dumping fuel, does that indicate an injector issue or a faulty sensor telling it to dump fuel?

 

[razorlab]

Thank you for the info! Any suggestions on things to look at? If something is dumping fuel, does that indicate an injector issue or a faulty sensor telling it to dump fuel?

Could be a lot of things. I can't remember, have you done a full scan of the car with bimmerlink yet?

Also, I thought you said LTFT and STFT looked fine after I asked you about them before?

 

[MOA90]

Could be a lot of things. I can't remember, have you done a full scan of the car with bimmerlink yet?

Also, I thought you said LTFT and STFT looked fine after I asked you about them before?

They were in the logs to @Twisted Tuning and I assumed they were good or they’ve changed. I’m not sure.

I have not scanned with BimmerLink but definitely can. I’ll report back.

 

[lucky phil]

Just a thought. All cylinders vary in their ability to convert a fuel and air mixture into efficient combustion. So many variables exist mechanically between the cylinders on the same engine that affect how well it ignites and burns it's fuel. DI engines in particular seem to be a bit combustion sensitive at start up and idle hence they all seem to throw misfires counts all the time and the ECU only responds with a fault response to advise the driver when the count reaches a pre determined threshold.
So my though is, in your case is it actually a global issue but only 1 cylinder is badly affected. So instead of focussing on 1 cylinder in particualr you should be focussing on a fault that is affecting the fuel delivery/air delivery on all the cylinders it's just that the #1 feels and reacts the worst due to sometime borderline mechanical differences that cause that particular cylinder to cross the reaction threshold. So something like a faulty engine temp sensor or MAF/MAP sensor or IAT sensor or fuel pressure regulator that affects the mixture on all cylinders but only 1 reacts due to minor mechanical variables. You get the idea.
Phil

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