Review on 🔧 Optimize Fuel Delivery: Delphi FP10021 Fuel Injection Pressure Regulator by Chris Beals

Purchased for a 2003 Chevrolet Silverado 5.3L VIN T with the following codes: P0300 Random/Multiple Misfires, P0172 System Too Rich Bank 1, P0175 System Too Rich Bank 2 Rough idle, difficult starting, delayed start and jet black smoke from the exhaust . These are the main indicators of a fuel injector gas pressure regulator failure. Physically check by removing the vacuum line from the regulator and checking for gasoline. If there is gasoline, the regulator is out of order. Replacing Difficulty and Dexterity Requirement: Locate EasyPop hood, power distribution panel and remove top cover. Locate and remove the fuel pump relay using the diagram on the underside of the panel. (Gently rock back and forth and pull to remove). Attempt to start the car a few times to relieve pressure in the fuel rail. Locate the pressure regulator on the fuel rail. Twist and gently pull to remove vacuum line. with a flathead screwdriver and gently pry off the edge of the C-clip. Once the edges are up, remove the C-clip (some have a retaining ring that needs to be removed with pliers). Gently twist and pull to remove the existing pressure regulator. Make sure the diaphragm and small black o-ring are removed. Apply light oil or WD40 to the o-rings of the new regulator to ease installation. Install the new regulator by gently pushing in and turning until it stops (some movement is normal and does not affect operation). Install a vacuum line. Install fuel pump relay. Install the power distribution panel cover. Turn on the ignition and allow the fuel pump to prime the fuel system (1 or 2 seconds). Clear all relevant engine codes with an OBDII scanner. The car should now start immediately. Congratulations! They just fixed a rough idle and some random misfires in the cylinders. A NOTICE. I've noticed a few reviews complaining about the ESC humming. This Delphi FP10021 Fuel Injection Pressure Regulator Part is an OEM GM regulator (like ACDelco) and is for vehicles with VIN T. If your vehicle has VIN Z (Flex Fuel) you will likely experience performance issues due to the lower pressure application VIN Z. Hope this helps!