00' V6 w/ 02' V8 Firebird fuel pump. Keep getting the same 3 fuel pressure regulator codes. Car passed emissions but failed OBD. Fuel gauge reads correct when it's not running but gets pinned on full at start up, then it just kind of bounces around while running. Something clicks in the throttle body every time I clear the code..........???????

 

pretty sure the fuel pressure on the ls1 is higher than the 3.8. also sounds like the fpr is sticking but it may be the flow of the ls1 fuel pump is overwelming the fuel pressure regulator. dont you 6 guys and gals forget to vote in the ride of the month race.

 

They use the same fuel pump =\

 

What are the code numbers? Looking at the V8 schematics I don't see any complications like a 2-speed fuel pump, a fuel pressure sensors, relays, etc. that make it different from a V6.

I'm wondering if a vapor recovery hose split or you didn't hook up something 100% right and the evaporative emission system is detecting a leak. On OBDII cars the computer tests the air tightness of the whole fuel system while you drive. Charcoal canister, tubing, tank, fuel cap, solenoid, everything... A loose fuel cap will turn on the SES/CE light.

BTW, that charcoal canister and vapor recovery system are *good* things. Before they were mandated (1972, I think in the 49 states; earlier in CA) a full 20% of a car's lifetime HC emissions came from raw fuel vapors escaping from the tank as the temp went up and down and the tank "breathed." Twenty percent and the car didn't even have to be running!

 

^^^ there is a sticky to test the vats system at the top of the lt1 section. thanks kal i didnt know if the 6 had lower pressure like the lt1s.