jhammer10

Have these two codes and hesitation under acceleration? Anyone else have/had this problem. Any help would be appreciated. Thanks.

joshtowal

Most likely it's a bad fuel pump, but there could be a lot of things that would cause those codes. My first check would be a fuel pressure test.

jhammer10

What is correct fuel pressure? 39 at the rail?

joshtowal

What year is your truck and what engine is in it?

joshtowal

Never mind...just saw you posted this somewhere else too.

Key on, engine off 35-45 psi
Engine running 28-50 psi

jhammer10

[QUOTE=joshtowal;3826177]Never mind...just saw you


Key on, engine off 35-45 psi
Engine running 28-50 psi[/QUOTe

Will check fuel pressure at lunch. Thanks for the help.

jhammer10

Checked fuel pressure. Took three key cycles to get fuel pressure. Key on is 40 and running is 33. When you goose it the pressure drops to 25?

joshtowal

It shouldn't take three key cycles to get it up to pressure, but stranger things can happen, I guess. Did the pressure bleed off pretty quickly (within a minute or two) with the engine off?

joshtowal

When you open the throttle, vacuum drop out, which closes the pressure regulator. If you take the vacuum line off the regulator while the engine is idling, the fuel pressure should jump by about 10 PSI. Also, see if there's fuel in the vacuum line.

Joseph McAtee

po 171 po 141are genraly intake gaskets try tune up first then go to intakes
i see alot of folks guessing at misfires like fuel pump go take a reading from the fuel rail then see