So im throwing a code 43. Its a fuel supply code. The cel doesnt come on at start up, but after driving for a while it comes on. it has a after market fuel pressure regulator. I was thinkin it might need adjusted. just seeing if anyone knows what else i could check.

THanks

 

anyone ?

 

Borrow a fuel pressure gauge from a parts store and check the pressure with and without the regulator vacuum hose attached.