2000 Chevy Silverado 1500 5.3 Fuel Pressure Regulator
 

Hey guy's, need help with an issue.

Just bought a 2000 Chevy Silverado 1500 5.3L. The fuel gauge was inop, and diagnosed as ad sending unit. Replaced the fuel pump assembly (which has the sending unit on it), and that fixed the gauge issue.

Second issue, engine stated hard after it was warm. Diagnosed as a Fuel Pressure Regulator (vacuum line was wet with fuel). Installed new fuel pressure reg. (Delphi) and that fixed the warm hard start / long crank issue.

BUT !! The fuel pressure regulator buzzes every 15-30 seconds and the buzz sends a vibration down the fuel lines. The sound is like a kazoo. It is the Fuel pressure regulator. Removed the vacuum line, buzzing stops. Installed a second Delphi F.P.R and same buzzing noise. Installed another brand from parts house (delco) and it still buzzes.

Any ideas as to what the issue is ?

After trying several regulators I tried a Borg Warner (BWD brand) and it works without issue.

Delphi brand - Buzzed
AC Delco - Buzzed

Odd - seems the later design became more like the C5.

Try Performance Trucks.net Those guys know GMT800/900 better than anyone. Often, upgrading to later factory design cures all.

I did recently purchase a 2000 Z71 which had been "diagnosed" by an Indy as needing 3 FP regulators. A quick lift of the bed and a new AC Delco Fuel Pump Assembly had it purring like new...