Is this a bad fuel pressure regulator?

Jerry Bransford said:
Both. A leaky check valve in the FPR causes the engine to not want to start right up again shortly after shutting it off. A leaky check valve in the fuel pump causes it to lose pressure more slowly so it tends to have starting issues only after it has sat a while like overnight or several hours.
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Okay, thanks. I'm going to try and replace the FPR with the Delphi I found and see if that works. I understand now that there is also a return system option some people install that is not much more in cost than the fuel pump itself, so I may go that route if further remedy is needed.

Thanks for all your help!
 
LMSeal said:
Okay, thanks. I'm going to try and replace the FPR with the Delphi I found and see if that works. I understand now that there is also a return system option some people install that is not much more in cost than the fuel pump itself, so I may go that route if further remedy is needed.

Thanks for all your help!
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There is no need for any sort of a fuel return system on a TJ.
 
I have a similar issue. After Jeep sits for a while about 3 blocks down the road it Boggs down and sounds like it’s going to die. Can give it some more gas for a couple seconds and then It runs as normal. Fuel pressure checks out fine. Thoughts?
 
Jerry Bransford said:
Depending on the problem, replacing just the fuel pump is normally a good way to go. The Bosch 69316 is the one I'd go for like at https://www.amazon.com/dp/B000BZL922/?tag=wranglerorg-20

The only time I'd not go with the fuel pump as the fix would be if the fuel system was losing pressure immediately after shutting the ignition off. In that case the fix is usually a new replacement fuel pressure regulator.

Whatever you buy, avoid store brands, Airtex, or Spectre. The only other brand I'd consider is Delphi.
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Hey Jerry,


Had an issue where I drove my 04 wrangler 4.0 for 15 minutes, shut it off, came back 5 minutes later and it would crank and crank and crank and wouldn't start. In the past year, it has gotten harder to start, but this is the first time where it didn't start. I drag the jeep back home with another vehicle and funny enough it starts up in the driveway.

That was all yesterday, and this is what I found today. Testing the fuel pressure, when I turn the key to the on position, pressure builds to 10 psi and almost immediately drops to 0. If I cycle the key multiple times I can build the pressure up to 20-30 psi, but again when I stop cycling the key, it drops back to 0. When the engine is running, pressure is around 50 psi, but goes back to 0 the second I turn the key off. Would this be the fuel pressure regulator as you mentioned above, or could it be the check valve in the pump itself?

Also when cycling the key and building up pressure to around 30 psi, I hear a hissing that sounds like it is coming from the gas tank. I don't appear to be leaking any fuel in the back.
 
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Avoid store brands like Duralast and cheap online brands like Airtex and Spectre. NAPA usually has a decent premium replacement, check www.rockauto.com for their better replacements too. I'd say Bosch or Mopar but I haven't seen them in a while. Based on the offerings on Rock Auto I'd go for the one from Standard Motor Products.
 
Jerry Bransford said:
Avoid store brands like Duralast and cheap online brands like Airtex and Spectre. NAPA usually has a decent premium replacement, check www.rockauto.com for their better replacements too. I'd say Bosch or Mopar but I haven't seen them in a while. Based on the offerings on Rock Auto I'd go for the one from Standard Motor Products.
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Thanks for the reply Jerry. Question, because I've seen both answers on different forums. Should you not be able to blow air through the fuel outlet of the fuel pressure regulator and have air coming through the fuel inlet on the bottom?
 
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