Do i need a fuel pump
Thread Starter
Teching In
Joined: Jan 2013
Posts: 6
Likes: 0
From: Cerro Gordo N.C
Do i need a fuel pump Ok my 04 tahoe is running like crap, codes 171 & 174 both banks lean. when you first start it up it runs good but my LTFT are 12 bank 1 & 13 bank 2 my STFT are good i think no more than -2 to +2 on both banks at idle. When the trucks get warm (10min) the LTFT goes 16+ on both banks & STFT are around 10 or 11 at normal driving (55mph). when i try to go WOT it falls on it's face bad LTFT goes 25 both banks & STFT go 55 both banks some times it wont get over 2 grand before cutting out, the longer it run the worse it gets. I did a smoke test nothing, did a fuel test 58-60 psi at idle if i slam the gas in park the gauge goes to 30psi fast if you try to hold it it will go to 0psi and only come back up to around 48-50 psi. but if you ease in the throttle very slowly it will take and not bog out but only 30 psi at wot. while driving the truck at 55mph the fuel trims are the same as above at 55mph & fuel psi is 58-60 psi. if you try to accelerate at 55 or from a dead stop the fuel trims go up & fuel psi starts dropping. So what could be causing this fuel pump or fuel psi reg? o i forgot i parked the truck at the first of the year cause of this & did knock sensors & intake gaskets & started back driving it the 15 of april ran great till the 28 it started back with the fuel psi prob.
