Strange fuel problem

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Jun 27, 2022 | 01:18 PM

llama

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5th Wheeling

Joined: Mar 2019

Posts: 25

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Strange fuel problem

I had removed my fuel rail and injectors to clean them. The truck had been sitting in the garage for a day, when suddenly fuel began to flow out of the disconnected fuel line. I quickly saw that I had left the key turned on and the fuel pump was running. I turned the key off and the fuel flow stopped. What would cause the pump to suddenly turn on? The truck was just sitting there untouched while I was watching a ball game in the garage.

Jun 27, 2022 | 01:52 PM

sandymane

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Joined: Oct 2016

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From: Houston/Sugar Land

Had the truck been in operating condition and the fuel pumps ran constantly with the key on, one common issue is PCM failure. When working with the components in your post, the battery should absolutely be disconnected. This doesn't answer your question but it would have prevented the issue.

Jun 27, 2022 | 02:09 PM

llama

Thread Starter

5th Wheeling

Joined: Mar 2019

Posts: 25

Likes: 2

Had not had the problem with fuel pump running before. The battery was disconnected at first. Then I reconnected it to check some electrical things and forgot to disconnect. Its just lucky I was there with a friend of mine watching Ole Miss win the College World Series

Jun 27, 2022 | 02:16 PM

sandymane

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Joined: Oct 2016

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From: Houston/Sugar Land

I certainly understand. When I replaced my intake manifold I forgot to connect the fuel line clips that slide over the lines and when I drove it, it died because the lines came off. . When I opened the hood I considered myself lucky also.

Jun 27, 2022 | 03:11 PM

sandymane

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Joined: Oct 2016

Posts: 6,185

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From: Houston/Sugar Land

With the key on engine off and battery connected the fuel pumps should run for 1 to 2 seconds and shut off. Again, in operating condition the PCM would be suspect if the pumps continue to run. Or, perhaps the fuel relay is stuck?? If it isn't, your PCM should be removed and check the capacitors for bloating and/or leaking. If you are cleaning injectors you probably have had some issues with the truck running. If so, perhaps it was the PCM causing the poor running or fuel problem.

Jun 27, 2022 | 03:32 PM

llama

Thread Starter

5th Wheeling

Joined: Mar 2019

Posts: 25

Likes: 2

Yep. I am planning on checking fuel relay tonight. Hope that is it. I took fuel rail off because the injectors had become clogged. I suspect a dirt-dobber nest from when i had the fuel rail off to paint the plenum. Yes, I didn't tape over the ends while it sat.