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90 vert starting hard

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Old May 9, 2025 | 04:53 PM
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Default 90 vert starting hard
I assumed it was the pressure reg. so I replaced it. That did no good. Any thoughts?
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Old May 9, 2025 | 06:03 PM
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Need more symptoms/info.
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Old May 9, 2025 | 08:07 PM
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Originally Posted by pltmgr
Need more symptoms/info.
OK. After the first start of the day, it starts fine. Accelerates fine. Idles fine. Has newish injectors. (Replaced a few years back) Doesn't smell flooded when it starts. Once it starts, you'd never know anything was wrong. At this point, I'm convinced the fuel is draining back to the tank. I thought the regulator would do the trick.
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Old May 10, 2025 | 12:15 PM
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This is the exact symptoms I had on my 96. It was the fuel pump. Borrow a tester and see. Dan
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Old May 10, 2025 | 07:30 PM
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Originally Posted by Whaleman
This is the exact symptoms I had on my 96. It was the fuel pump. Borrow a tester and see. Dan

As I understand it now, the check is in the fuel pump. I thought it was in the regulator.
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Old May 10, 2025 | 08:53 PM
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Originally Posted by wedgeheaded
As I understand it now, the check is in the fuel pump. I thought it was in the regulator.
Yes, there is a check valve in the pump. My fuel pump just had low pressure that showed up 5 minutes after putting a gauge on it. A leaking injector can also look like a bad check valve. Dan
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Old May 11, 2025 | 07:47 AM
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Do you hear the 2 seconds of fuel pump when you first turn the key to the on position, engine off ? If not, you are starting on the oil pressure switch instead of the ECM / fuel pump relay.
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Old May 11, 2025 | 04:31 PM
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Originally Posted by Vets-Vet
Do you hear the 2 seconds of fuel pump when you first turn the key to the on position, engine off ? If not, you are starting on the oil pressure switch instead of the ECM / fuel pump relay.

Yes, I have the fuel pump noise. When it does start, it stumbles and dies. It takes several tries to get it running but then it's fine. I
m pretty sure it's fuel related. Good thought though.
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Old May 11, 2025 | 05:20 PM
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Originally Posted by wedgeheaded
Yes, I have the fuel pump noise. When it does start, it stumbles and dies. It takes several tries to get it running but then it's fine. I
m pretty sure it's fuel related. Good thought though.
Are you aware you can borrow a pressure checker for free from like Autozone's and others? Dan
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Old May 31, 2025 | 09:06 PM
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Last edited by wedgeheaded; Jun 1, 2025 at 08:28 AM.
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