2000 Chevrolet Silverado LS, 5.3 engine. Intermittently, i turn the key over and there is a long cranking cycle without starting. When this happens, I cycle the key off for a few seconds. Turn it back on for a few seconds, then it cranks over and starts right up. It has a new AC Delhi fuel pump. What might be the issue?
Long cranking, 2000 Silverado
- Thread starter otis24
- Start date
Fuel pressure regulator. Does it have the one on the driver's side of the intake manifold?
If the fuel pump was just replaced, I'd suspect it might have something to do with that.
Why was the pump replaced? If you suspected you had a bad pump, maybe the problem was actually a bad fuel pump relay or something. A weak battery in cold weather can contribute to relays not latching in properly, due to excessive voltage dip when the ignition is turned on.
Why was the pump replaced? If you suspected you had a bad pump, maybe the problem was actually a bad fuel pump relay or something. A weak battery in cold weather can contribute to relays not latching in properly, due to excessive voltage dip when the ignition is turned on.
Long cranks are usually fixed by, changing the fuel filter, new 12v and spark plugs.
The battery can be tested so just throwing a battery at it and wasting $200 is preventable.
The battery can be tested so just throwing a battery at it and wasting $200 is preventable.
Your '05 LQ4 Yukon Denali doesn't have vacuum referenced fuel rail mounted FPR.
One good lean pop/backfire can rupture the diaphragm in a vacuum referenced FPR.....A weak/failing fuel pump is generally what causes a lean backfire.
Doubtful. The regulator keeps the pressure from going too high. If it were ruptured, the engine would run extremely rich all the time. He needs to verify that the pump is delivering proper fuel pressure. Sounds like a borderline new pump or a wiring issue to the pump where the pump is not running at 100 percent.
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Spray starting fluid in the intake while trying to start cold. Does it fire sooner?
According to Google there is a fuel pressure regulator on the driver’s side under the engine cover.
New spark plugs, new fuel pump, fairly new battery.
My guess was that the Fuel Pressure Regulator has a bad check valve. Had a vehicle on the lot of the dealership where I worked that did that. Don’t know that for sure.
Can’t remember why I replaced the fuel pump. Seems like it was acting up. Tank had to be dropped to replace a rear leaf spring so figured just as well replace it while the tank was down.
Can’t remember why I replaced the fuel pump. Seems like it was acting up. Tank had to be dropped to replace a rear leaf spring so figured just as well replace it while the tank was down.
Could be a bad crank sensor. Have you scanned the ECM for codes?
Haven’t scanned for codes but I will.
Hmmm, not really, it actually increases the flow to the injectors by restriction under low vacuum, like when you hit the throttle.
