bad fuel gauage or regulator

[tonys87]

i added a couple of psi of fuel yesterday when i noticed that when i put the line back on it only drops about 2spi. ive read it should be half of what your vacumm gauge is reading if thats so i was at 14hg which would mean i should be at 35-36 line on but im more around 39-40. could it be the gauge,regutaor or is it something else..i also checked for vacuum leaks and didnt find any

 

[QUIP'6']

i added a couple of psi of fuel yesterday when i noticed that when i put the line back on it only drops about 2spi. ive read it should be half of what your vacumm gauge is reading if thats so i was at 14hg which would mean i should be at 35-36 line on but im more around 39-40. could it be the gauge,regutaor or is it something else..i also checked for vacuum leaks and didnt find any

you can try another vacuum source temperary to see if that line is collapsed or bad. ot try a vaccuum pump and see if it goes below 2 psi if it doesnt then i would say the regulator is bad. is it a new adjustable one?

 

[tonys87]

ok i replaced my fuel pressure gauge with a hood mount one and it still only drops 2psi. i checked the vacuum line with a vacuum/boost gauge and its at 13hg so i think the vacuum line is fine,unless i should have more vacuum..now i think it the fuel pressure regulator its a accufab unit is there anything that i may try to fix it?

 

[tonys87]

now i noticed that when i turn the car off the fuel psi drops to 30 then creeps right back up after a couple of minutes back to 40psi..all while the engine is not running..whats going on?

 

[QUIP'6']

now i noticed that when i turn the car off the fuel psi drops to 30 then creeps right back up after a couple of minutes back to 40psi..all while the engine is not running..whats going on?

thats normal i have a hood mounted one and 2 days later it shows zero then the next day it shows 30 and then it just keeps changing when the car is off. i think it is air

 

[tonys87]

update i sent out the regulator to get rebuilt at accufab and the problem is still there i cant set it any lower then 43psi is this normal? and it still doesnt drop the psi with the vacuum line on..please help need more ideas on what the problem might be

 

[Scott Atk]

Check for a restriction in the return line. Follow the line out the bottom of the regulator. Check for any kinks, etc.
I would also put a vacuum gauge directly on the line going to the regulator. But if it won't adjust lower than 43 with the line off, I'm thinking restriction in the return line.