Dealer not honoring warranty work..2018 5.3 Yukon issues

[smokey_mountain]

I am in NC, RPM Motorsports in Garner NC are well respected by the GM Corvette and other GM vehicle performance crowd. I took it to them and they found 4 injectors in bank #2 to be out of spec, but I asked them to stop diagnosing as it was on my dime. Entire bank of injectors is most likely not defective but rather there could be issues with vacuum on bank #2 or with running too rich and O2 sensors. Folks here are telling me that injectors cannot be failing without a code due to strict emission controls in the truck but RPM Motorsports guys found bank #2 to be 30+% out of spec on the injector balance test and zero codes... How is that possible, I do not know but I posted RPM results here, they are confident on their findings. RPM told me that to really find out what is wrong one needs to do leak down test, etc. I was already $300+ in rental and mechanics fees, I stopped in hope that diagnostics from RPM will be enough from GM dealer to fix but no dice... no codes, no issues per the GM.

Hey Dmitry, where do you live? Why not get with someone more knowledgeable about autos and have them check it out with you? Live in Florida by chance?

 

[swathdiver]

I am in NC, RPM Motorsports in Garner NC are well respected by the GM Corvette and other GM vehicle performance crowd. I took it to them and they found 4 injectors in bank #2 to be out of spec, but I asked them to stop diagnosing as it was on my dime. Entire bank of injectors is most likely not defective but rather there could be issues with vacuum on bank #2 or with running too rich and O2 sensors. Folks here are telling me that injectors cannot be failing without a code due to strict emission controls in the truck but RPM Motorsports guys found bank #2 to be 30+% out of spec on the injector balance test and zero codes... How is that possible, I do not know but I posted RPM results here, they are confident on their findings. RPM told me that to really find out what is wrong one needs to do leak down test, etc. I was already $300+ in rental and mechanics fees, I stopped in hope that diagnostics from RPM will be enough from GM dealer to fix but no dice... no codes, no issues per the GM.

Ok. What the GM Tech wondered was if the test on Bank 2 was run at the same temp as Bank 1. If one was run first on a cold motor and then the other once up to temp, they will certainly be different and there is nothing wrong with that. If they did that and are humble folks, they will admit such an error.

Why don't you get one of those Bluetooth OBDII adapters from Amazon and download the Torque Pro app for your phone. Then you can monitor engine functions yourself and look for trouble, like Fuel Trims and injector pulsing. Post data here or at Performance Trucks and you'll know pretty quick what might be amiss.

 

[smokey_mountain]

Truth is that RPM Motorsports's is a GM performance shop and the tech who diagnosed the problem is 15+ GM tech at the dealership as master tech, they are readily available to answer any questions, I gave all info to Hendrick GMC and provided all the phones. RPM Motorsports did warm up the truck before they measured to 140 degrees, he has all data from that GM-approved machine that he used to measure injector balance.

Thank you @swathdiver I do have OBD adapter and I ran OBD Fusion on iPhone for a day. I do not see a place in that app to see Fuel Trims and injector pulsing data there. I think Torque Pro is next app to buy. I will run it today.
here is a video from OBD Fusion

Ok. What the GM Tech wondered was if the test on Bank 2 was run at the same temp as Bank 1. If one was run first on a cold motor and then the other once up to temp, they will certainly be different and there is nothing wrong with that. If they did that and are humble folks, they will admit such an error.

Why don't you get one of those Bluetooth OBDII adapters from Amazon and download the Torque Pro app for your phone. Then you can monitor engine functions yourself and look for trouble, like Fuel Trims and injector pulsing. Post data here or at Performance Trucks and you'll know pretty quick what might be amiss.

 

[Bob2C]

I have OBD fusion and just realized user defined PID’s can be imported into the app. Now I’m going to run it

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[smokey_mountain]

You are a hero @Bob2C ! I will do that too!

I have OBD fusion and just realized user defined PID’s can be imported into the app. Now I’m going to run it

Sent from my iPhone using Tapatalk

 

[Bob2C]

You are a hero @Bob2C ! I will do that too!

Go to settings, user defined PID, then click menu on upper right then select import built in PID

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[smokey_mountain]

Yes imported them, thank you, @Bob2C

 

[smokey_mountain]

I have tried custom PIDs for GM for injector balance but I am getting all values as zero, OBD Fusion does not see these custom user PIDs, suspect I am doing something wrong. However logs are created now and attached.
https://drive.google.com/file/d/1T2FGS2bybzxairxZbO6_MZ8lB2cnd6ni/view?usp=sharing

View attachment 234257

In the monitor section of OBD Fusion I see misfires, it changes but I have seen as high as 6 misfires in 7 minute ride, on #7 and 1-2 on other. I suspect it is totally normal but I do not know how to interpret.



@swathdiver calling on your expertise if possible.
@Bob2C do you see user-defined PIDs value in your OBD Fusion?

 

[Bob2C]

I have tried custom PIDs for GM for injector balance but I am getting all values as zero, OBD Fusion does not see these custom user PIDs, suspect I am doing something wrong. However logs are created now and attached.
https://drive.google.com/file/d/1T2FGS2bybzxairxZbO6_MZ8lB2cnd6ni/view?usp=sharing

In the monitor section of OBD Fusion I see misfires, it changes but I have seen as high as 6 misfires in 7 minute ride, on #7 and 1-2 on other. I suspect it is totally normal but I do not know how to interpret.

https://drive.google.com/file/d/1_23Yz1DBvs5sjhxIRhimFJXSP2F8WpzC/view?usp=sharing

@swathdiver calling on your expertise if possible.
@Bob2C do you see user-defined PIDs value in your OBD Fusion?

I have not had a chance to run the software. I got caught up in trying to find a coolant leak in my other car. I will try to run it tomorrow.


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[smokey_mountain]

This is what I am seeing on another 7 min ride, looks like Bank 2 is not doing well Cyl #7 is consistently showing misfires