Chevrolet Repair: 1997 Chevy 1500 starts hard, fuel pressure gauge, pressure relief valve

Question
I have a 1997 Chevy 1500 305TBI with 110,000 miles. It seems that after the truck sits for a 2 days or so, it starts hard. After cranking it way more than normal, it runs fine. Truck will start 4-8 hours later. Still seems like it starts a touch harder than it use to but it starts much better than when it sits for 2 days. I replaced the filter. Some people are suggesting the pump, The pump runs for several second when turning the key on. If I press the fuel pressure relief valve after the pump turns off, I get a little dribble of fuel. If I press the valve when the pump is still running, it shoots fuel 12 inches in the air. So it appears to me that the pump is working. Another person suggested it could be the regulator. Please, any suggestions. Thank you, Steve Hinkley

Answer
Hi Steve, Yes it could be the pump or the regulator. You need to test the system, install a fuel pressure gauge on the test port and turn the key on without starting the engine. The gauge should read around 55 to 60 psi and hold steady not dropping off. If it drops off then either the pump is bad or the regulator. To find out which one you need to pinch off the return hose and do the test again. You can get the hose where the lines come down next to the transmission. If after pinching off the hose, if it still drops then it is the pump.

Hope this helps

Have a Great Day       Mark