Bad direct injector?

[MOA90]

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

I haven’t thought about it like that but have definitely been wondering what sensor it could be. I just scanned it with BimmerLink and didn’t get anything that I didn’t already know. I did see that cylinder 1 is still misfiring more than the rest even after moving that spark plug and coil to other cylinders.

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[lucky phil]

I haven’t thought about it like that but have definitely been wondering what sensor it could be. I just scanned it with BimmerLink and didn’t get anything that I didn’t already know. I did see that cylinder 1 is still misfiring more than the rest even after moving that spark plug and coil to other cylinders.

Looking back over your post history are you sure this thing hasn't got a leaking head gasket into #1 cylinder? Initially you will see very little coolant loss even not noticeable. It sounds awfully like the Ecoboost engines when they were leaking coolant into the cylinder. In that case it was the worst after the engine fully cooled and left overnight. After the first start of the day and restarts after short shutdowns they were generally OK when the leakage wasn't too bad at the beginning. As it got worse then the symptoms got a LOT more graphic. The leakage scenario was a little unusual in the Ecoboost case where they leaked into the cylinder at the bore bridge area only during the engine cool down phase. When the engine was at operating temp it was fine. Might be worth doing a Borscope of that cylinder. Doesn't take long and is easy to do. I have an Oasis scientific articulating borescope but there are cheaper options out there for a one off look or any decent workshop should be able to do it for you.
Phil

EDIT.....Here's an image of the Head gasket on an Ecoboost engine in the initial stages of leaking coolant into the cylinder. The head on the top and the cylinder below with the head gasket sandwiched between with leakage indications. No symptoms at this stage.

 

[MOA90]

Looking back over your post history are you sure this thing hasn't got a leaking head gasket into #1 cylinder? Initially you will see very little coolant loss even not noticeable. It sounds awfully like the Ecoboost engines when they were leaking coolant into the cylinder. In that case it was the worst after the engine fully cooled and left overnight. After the first start of the day and restarts after short shutdowns they were generally OK when the leakage wasn't too bad at the beginning. As it got worse then the symptoms got a LOT more graphic. The leakage scenario was a little unusual in the Ecoboost case where they leaked into the cylinder at the bore bridge area only during the engine cool down phase. When the engine was at operating temp it was fine. Might be worth doing a Borscope of that cylinder. Doesn't take long and is easy to do. I have an Oasis scientific articulating borescope but there are cheaper options out there for a one off look or any decent workshop should be able to do it for you.
Phil

I will definitely check on that. One thing to note is that this happened all at once. I did a pull and it cut power, then couldn't idle without sounding like a Subaru ever since. That immediately had me checking for a coupler or hole in my charge pipe or intake piping. I've gone through all of that and I don't see any issues.

 

[razorlab]

I will definitely check on that. One thing to note is that this happened all at once. I did a pull and it cut power, then couldn't idle without sounding like a Subaru ever since. That immediately had me checking for a coupler or hole in my charge pipe or intake piping. I've gone through all of that and I don't see any issues.

Have you scoped your cylinders yet?

 

[MOA90]

Have you scoped your cylinders yet?

when I re-gapped my plugs I shined my light and didn't see anything. I will definitely be scoping them and see what I can find.

 

[MOA90]

I've scoped cylinder 1 & 2 and couldn't see much but it didn't look the best in regards to carbon build up. My newish spark plugs are already dark. I've swapped MAF and O2 sensors which didn't help. I've tried a new tune that disabled port injection that didn't help. I'm thinking of trying a smoke test, and pulling my direct injectors next. Any suggestions or thoughts?

 

[dismii]

Good Morning Gentleman I found the issue to my supra same concerns as most of the ppl on this thread,

i found my issue to be on my cam ledge, bolt was stretched replaced it with both brand new bolts and found issue to be fixed up to 98% , i recommend you guys check your cam bolts common issue on this vehicle

 

[MOA90]

Good Morning Gentleman I found the issue to my supra same concerns as most of the ppl on this thread,

i found my issue to be on my cam ledge, bolt was stretched replaced it with both brand new bolts and found issue to be fixed up to 98% , i recommend you guys check your cam bolts common issue on this vehicle

Interesting, what were your codes? What did your fuel trims look like?

 

[dismii]

Fuel trims were perfect, same codes as the original post, Look up my insta @dismii_ i can send you videos and pictures

 

[MOA90]

Fuel trims were perfect, same codes as the original post, Look up my insta @dismii_ i can send you videos and pictures

Oh ok, we seemed to have some differences because my fuel trims were very rich.

 

[MOA90]

I just did a smoke leak test over the weekend and didn't find any leaks. Everything seems to point to a fuel injector. The fact that it is dumping fuel, it's not a boost leak, not an O2 sensor, MAF sensor nor does it seem to be plugs/coil packs. The only thing I haven't done is replace the gas but because of the sudden nature that the issue presented itself I doubt it's fuel. I'm going to pull the fuel injectors and test them and I'll report back. If anyone has any other suggestions I'm all ears.

 

[MOA90]

I saw this video from Kern and decided to see if my fuel pressure dropped or climbed after a heat cycle and it rose which indicates I don't have a bad fuel injector. I also got fresh gas today just to make sure it wasn't that and it wasn't. This issue has been perplexing and I'm really starting to run out of ideas. I am going to check compression and make sure I did the smoke leak test correctly but if anyone has any suggestions I welcome them.

 

[Thraxbert]

Have you done a combustion leak test? This would rule out head gasket, cracked head, and some cases of cracked block.

Have you logged the pressure of your LPFP? I would be curious to see its PSI from cold start to fully warm oil (>190F). Perhaps you have an EKP module that has gone to lunch.

If you're running PI, how is that set up? Do you have a secondary LPFP? How is it being triggered? You're sure that PI injector isn't stuck open? If you're on a Motiv Reflex+, are you running one of the firmware that (OOPS!) caused injectors to get stuck at 100% duty cycle?

 

[MOA90]

Have you done a combustion leak test? This would rule out head gasket, cracked head, and some cases of cracked block.

Have you logged the pressure of your LPFP? I would be curious to see its PSI from cold start to fully warm oil (>190F). Perhaps you have an EKP module that has gone to lunch.

If you're running PI, how is that set up? Do you have a secondary LPFP? How is it being triggered? You're sure that PI injector isn't stuck open? If you're on a Motiv Reflex+, are you running one of the firmware that (OOPS!) caused injectors to get stuck at 100% duty cycle?

I haven't done a compression check but plan on doing that this weekend.

I haven’t logged my LPFP pressure but I watched it today and it ranged from 1800 or so at idle to 5000 when driving.

My port injection was turned off in a tube revision and still had the same issues so I’m fairly confident that can be ruled out.

I haven’t heard of the EKP module before you mentioned it.

 

[MOA90]

Is 5000 psi when cruising too high?

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