97 s10 2.2
bogs/sputters after 3500rpms
Live data shows that fuel system one is stayingstay"OL" open loop even after the truck is fully warmed up to operating temp.....42psi fuel pressure at idel, 45/46 under throttle....
longft1 and shrtft1 are both "0"
No engine codes, just sputters past 3500rpms and has no power to get out of its own way....any advice is appreciated....thanks in advance
(both oxygen sensors good, and egr is new)
map and tps both working well also going by live data

 

had an 02 4.8 that did that. turned out to be the fuel pump. i think what happened was the rubber hose at the pump had spung a leak. it would keep up fuel pressure when you would idea but when the truck was under load the demand for fuel was much higher than just under throttle. you couldnt even pass anything, the rpms would pick up but it would go no where. not sure if its the same situation but it might be a good place to start

 

Even with the fuel pressure numbers being dead on.....not trying to second guess yourself, simple asking, thanks

 

im with you on the numbers. and i cant remember how mine tested but im almost certain the pump tested good also and was the last thing i replaced. i hate throwing parts at something but after replacing the fuel pressure regulator and the problem not going away i was pretty limited on other options. im not certain if your pump is bad but just revving the engine wont consume as much fuel as trying to floor it while passing someone. so the fuel pump might be putting out the right amount of pressure due to the lower volume required but if you have to up that volume to give the engine more power the pump cant keep up. i would try to set up the fuel pressure gauge so its visible with the hood shut so you can take it on the road and then floor it and see what happens