mildtowild
Custom Upholsterer
My fuel pressure is not responding to changes in boost levels. It stays right at where i set it with the vacum off. I can not find a vacum leak, any thoughts? Maybe the diaphram in the APFR?
Fuel Pressure not changing
- Thread starter mildtowild
- Start date
mattw
Active member
Re: Fuel Pressure not changing
Sounds like its a bad FPR.. I'd apply air pressure to the FPR from an external source with the engine idling and see if the FP goes up. I can't remember but I think those Mighty-Vac pumps will provide vacuum or pressure.
That way you can be 100% sure that the FPR is seeing positive air pressure..
Sounds like its a bad FPR.. I'd apply air pressure to the FPR from an external source with the engine idling and see if the FP goes up. I can't remember but I think those Mighty-Vac pumps will provide vacuum or pressure.
That way you can be 100% sure that the FPR is seeing positive air pressure..
SY2932
Administrator
Re: Fuel Pressure not changing
If you can change the pressure by adjusting the screw on the top or the regulator, the diaphragm should be ok. With the truck running, can you feel suction on the end of the vacuum line for the pressure regulator? Sounds like a vacuum problem to me. This is what one looks like inside if you have never had one apart before:
As you can see, there's not much to one...
If you can change the pressure by adjusting the screw on the top or the regulator, the diaphragm should be ok. With the truck running, can you feel suction on the end of the vacuum line for the pressure regulator? Sounds like a vacuum problem to me. This is what one looks like inside if you have never had one apart before:
As you can see, there's not much to one...
mildtowild
Custom Upholsterer
Re: Fuel Pressure not changing
found the problem, a melted vac line.
found the problem, a melted vac line.
![Quickstop [UK]](/data/avatars/m/5/5165.jpg?1570199786){kind=avatar}
Quickstop [UK]
Combating adversyty.
TNPhoon
1of28
Re: Fuel Pressure not changing
Guessing the one that is pictured taken apart?
No, not stock.
Guessing the one that is pictured taken apart?
No, not stock.
SyTyAddict
Member
Re: Fuel Pressure not changing
The one taken apart looks like a Kirban afpr, but the PTE one also looks pretty much identical.
The one taken apart looks like a Kirban afpr, but the PTE one also looks pretty much identical.
powercat6
Active member
Re: Fuel Pressure not changing
There's a pic of a stock FPR in this link if that's what you're looking for; third picture.
http://www.syty.net/forums/showpost.php?p=878868&postcount=1
There's a pic of a stock FPR in this link if that's what you're looking for; third picture.
http://www.syty.net/forums/showpost.php?p=878868&postcount=1
dgoodhue
BuSTeD 4.3
Re: Fuel Pressure not changing
Did you use the autozone silicon vacuum hoses? If you have any other vacuum lines from the same source I would replace all of them.
Did you use the autozone silicon vacuum hoses? If you have any other vacuum lines from the same source I would replace all of them.