No fuel pressure

Jrice24

New Member
Joined
Aug 24, 2022
Messages
3
Location
Virginia
Hey guys, I have a new to me 95 wrangler Sahara, when purchased, PO stated he had just replaced the fuel pump, distributor cap, rotor, and camshaft position sensor. While driving it died on me, kind of sputtered out, and wouldn’t restart. It will fire and run for 2 seconds then die. I’ve read a lot of posts on the subject just wanted some feedback before I drop the tank to replace the fuel pump. Here’s what I’ve checked/done so far:

1. Put an additional 5 gal gas in the tank in case the gauge was bad, gauge moved after filling. Currently shows 3/4 tank.

2. Swapped fuel pump relay with known working horn relay.

3. Checked grounds, cleaned terminals, all seem good.

4. I have spark to all 6 cylinders according to in-line spark tester. This should rule out crankshaft position sensor if I’m not mistaken?

5. Checked old fuel filter, it was installed in the right direction. Replaced it with new fuel filter, double checked correct direction.

6. Connected fuel pressure gauge to schrader valve. Turned key to igntition on, zero pressure. Cranked engine, zero pressure.

7. Bypassed the relay to turn the fuel pump on and opened the bleeder valve on the tester. You can hear pump running, fuel comes out of the schrader valve at a rate of about 150-200ml in 30 seconds. I’ve read this should be around 500ml in 30 seconds, not sure if that’s correct.

8. Replaced fuel pressure regulator.

I’ve read about ECU issues preventing priming, but I should be able to rule this out as well since I bypassed the relay and turned the fuel pump on and it still won’t start or build pressure.

I’ve read there is a check valve in the pump itself that could go bad, which could explain why I’m getting fuel to the rail but not building any pressure in the system. Pump is around 6 months old but is this likely the cause, or is there something else to check first? Thanks
 
Are you hearing the fuel pump
cycle on when you turn the key?
Honestly I can’t say for sure over the sound of the buzzer when I turn the key, but I don’t think so. My thought is even if it doesn’t prime the lines when the key is turned on, once I supply constant power to it by jumping the relay terminal it will pump fuel to the fuel rail, but there is still no readable pressure in the rail.
 
SoundHave you changed the fuel filter?
Honestly I can’t say for sure over the sound of the buzzer when I turn the key, but I don’t think so. My thought is even if it doesn’t prime the lines when the key is turned on, once I supply constant power to it by jumping the relay terminal it will pump fuel to the fuel rail, but there is still no readable pressure in the rail.
if jumping it doesn’t send pressure you may need a new fuel pump. Also change the fuel filter for good measure.
 
Thanks, I did replace the fuel filter. From what I understand there’s a check valve in the pump that holds that pressure, if it’s bad it would create the condition I’m experiencing. The fuel pump is only 6 months old though, so that sucks
 
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Thanks, I did replace the fuel filter. From what I understand there’s a check valve in the pump that holds that pressure, if it’s bad it would create the condition I’m experiencing. The fuel pump is only 6 months old though, so that sucks
Hi, just reading your post, is the attached pic of my fuel filter enough to warrant a replacement?

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