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Discussion Starter · #1 ·
Have a 98 C3500 2WD, 5.7L. Purchased vehicle a month ago. Drove it down from Michigan to North Carolina and it ran great. Has 56K. Last weekend went to start and it would just crank and not start. Has plenty of fuel. Did not pop any DTC codes. I put new fuel filter on. I hear fuel pump cycling. But, when I put fuel pressure gage, I get no reading. So, I double check my gage on another vehicle and it is working fine. Prior to connecting fuel filter, I cycled fuel pump and it put out like a fire hydrant. So, I then I suspect a blockage in fuel line from filter to throttle body. I remove Schrader valve and clean and also blow air into fuel line to clean any potential blockage. All seemed clear. I am getting fuel to throttle body. But again, no pressure reading on fuel pressure gage. So I suspect that the fuel pump is pumping but not at sufficient pressure. Am I on the right track. Appreciate any help......thanx...
 

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Welcome to the club. May have a bad fuel pressure regulator.
 

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I thought that, but the pressure regulator is after the the pressure check valve. So not quite sure that would be the cause. I've read here and also the service manual that a fault pressure regulator will give high or low pressure readings. Right now, I am not getting any pressure readings at the pressure check valve. Thanx for responding..............
 

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This is rare but I have seen it a couple times where on most chevys there is a small rubber hose between the fuel pump output line going into the sending unit that rots out and gets a hole in it so its not pumping the fuel out of the sending unit. It could just be something as simple as that so it might be worth pulling the sending unit out if you cant find anything else.

Good luck!
 

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Welcome to the club Bertram. X2 on the FP regulator. It doesn't matter that the regulator is after the pressure check valve. If it's open (faulty) & allowing full flow to return, it won't show any pressure on your guage.

**edit,, to clairify... if your press regulator was before your press check valve for the guage, then you would effectively be measuring the return pressure rather than the supply pressure.

This could also be what Crispyt has posted, but like he said it is rare, & since your pump is putting out like a fire hose I would save that for last cuz it's a pita to access the fuel pumps.
 
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