Power loss and sporadic stalling

[richard wysong]

Does it still run better after shutting it down and restarting?

[noobie]

16 hours ago, richard wysong said:

Does it still run better after shutting it down and restarting?

Yes it does. But, not for very long. 

[richard wysong]

so there's a good possibility that the sock in the fuel tank is restricted as you already checked the cat back pressure by removing the 02s. Do a volume test of the fuel pump. I'm wondering if the bad plugs masked any improvement you might have realized by testing with the 02 sensors removed. If it passes the  fuel volume test you might try to find a gauge to check the exhaust back pressure. A misfire from bad plugs can ruin a cat as the unburned fuel ends up burning in the cat causing them to overheat and melt the substrate

Edited November 21, 2022 by richard wysong

[noobie]

Thanks for all the input folks. I never mentioned a tune being on the truck, because I thought there wasn't one on it... turns out the was a parameter set up to manage the fuel pedals response. Truck has been working fine since this was noticed. It's a bitter sweet thing.