Running rich after replacing all injectors

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RocketcCutlass

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Ok so all sensors have been replaced a while ago except crank sensor. Plugs and wires done as well. All GM/AC Delco parts. I replaced all injectors last week and it’s running super rich. So much so it through the P0172, P0175, and P0420 low catalyst efficiency codes this morning. What’s weird is I put the range afm disabler on right after running it monitoring the fuel trims the day I changed the injectors and it didn’t throw any codes at all after a couple hundred miles of driving. This morning on the way to work, just a 10 mile drive, is when it threw the codes. It was only after taking off the range module to monitor the fuel trims to see if it learned new ones. I had been driving all week with the range module on with no issues. I’m wondering if the range module is adjusting the fuel trims enough to stop it from throwing codes. Also it run’s absolutely fine and smooth as butter. Oh and I also did a crank sensor relearn, fuel trim relearn and all the other relearns I could do with my innova tool. Any ideas?
 

swathdiver

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Both banks rich and it threw a dead cat code for one side. It may need some time to adjust. Did you pull a plug from each side?

What year and engine are you driving and what is the part number of the injectors?

Have you run any Long Term Fuel Trim graphs while idling and driving? I'd be looking for vacuum leaks too.
 
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RocketcCutlass

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It’s a 2011 Tahoe LMG 5.3. The injectors were the factory GM ones that I bought new from rock auto and matched the numbers of the ones I pulled off. I didn’t graph the fuel trims but they stayed at -30.5 driving on both banks and went down to -25.2 when idling. I did not pull a plug. The exhaust doesn’t smell rich and like I said it runs extremely smooth.
 

swathdiver

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It’s a 2011 Tahoe LMG 5.3. The injectors were the factory GM ones that I bought new from rock auto and matched the numbers of the ones I pulled off. I didn’t graph the fuel trims but they stayed at -30.5 driving on both banks and went down to -25.2 when idling. I did not pull a plug. The exhaust doesn’t smell rich and like I said it runs extremely smooth.
Ok, so the injectors are 12613411 or 217-3411? That's the current number anyway.

Having said that, those trims are the sign of a massive vacuum leak. Can you see the color portion of your intake gaskets? Did you check all the connections between the air cleaner and the throttle body? No connectors on the top of the intake were forgotten? Brake booster line?
 
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RocketcCutlass

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It’s not running like it has a vacuum leak. Also I put the range module back on and the fuel trim codes went away on their own after just 15-20 miles of driving.
 

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