Fuel Issue?

[99TahoeOwner]

I have a 1999 Tahoe LT with a 5.7L engine. It only has 44,000 miles since it was in storage for about 18 years before we got it.

I've been having intermittent issues with it starting. It seems like a fuel issue because the engine will crank but not start. I can prime the pump by turning the ignition to the on position a few times and then it will start right up and run fine. I put a pressure gauge on it and found intermittent low pressure, but holds pressure, so I swapped out the fuel pump. That hasn't fixed the problem. This is the second pump I've put on in the past 7 months. I replaced the original pump because it was making a squealing noise.

My next thought is that it could be the fuel pressure regulator, but that looks like a pain to change, so I thought I'd get some other opinions from y'all.

Is there anything else that might be causing this issue I should check out before I go to the trouble of removing the manifold cover to replace the regulator?

And if I do dive into the manifold to change the regulator, is there anything else there that I might think about changing on this 21-year-old truck just as a precaution?

Thanks for your help.

Dan

 

[GreyStone]

fuel filter

 

[drakon543]

also test the power going to the fuel pump. if your relay is going bad or just a bad connection the pump wont stay running properly. as far as the manifold job make sure you know exactly how the distributor goes back in. 1 tooth off and you could be fighting it for a while to get it to line back up correctly. also check the distributor gear for wear.

 

[OR VietVet]

The fuel pump relay should always be done at the same time as a fuel pump and the filter as well.

First one is the 4 door model: https://www.rockauto.com/en/moreinfo.php?pk=1330512&cc=1353721&jsn=2273

Now the 2 door model: https://www.rockauto.com/en/moreinfo.php?pk=1792036&cc=1353721&jsn=2276

Filter: https://www.rockauto.com/en/moreinfo.php?pk=91205&cc=1353721&jsn=2295

Relay: https://www.rockauto.com/en/moreinfo.php?pk=4759320&cc=1353721&jsn=2365

When you say you have to prime it by turning key on and off, it sounds like the system has a leak that bleeds off. That should be checked before parts replacement. If it cranks and will not start, what is it missing? Fuel pressure or spark?

The sky is the limit as to what you do while having the manifold off. Quality parts are key.

 

[99TahoeOwner]

I started with something easy so yesterday I added an injector cleaner to the tank and this morning I changed the filter. Keeping my fingers crossed. Before I changed it, I tried starting it and of course, it started right up. This is the first morning in a week that it's done that. Figures.

If that doesn't work, I'll move on to checking the power as Drakon543 suggested. I'm pretty new to working on cars so I'll have to Youtube it to see how to do that.

Thanks for the links, PNW VietVet. I had tried to pick up a relay when I got the filter, but my local parts store didn't have it, so your link will come in handy. And, BTW, thank you for your service.

 

[Joseph Garcia]

I started with something easy so yesterday I added an injector cleaner to the tank and this morning I changed the filter. Keeping my fingers crossed. Before I changed it, I tried starting it and of course, it started right up. This is the first morning in a week that it's done that. Figures.

If that doesn't work, I'll move on to checking the power as Drakon543 suggested. I'm pretty new to working on cars so I'll have to Youtube it to see how to do that.

Thanks for the links, PNW VietVet. I had tried to pick up a relay when I got the filter, but my local parts store didn't have it, so your link will come in handy. And, BTW, thank you for your service.

Whenever you need replacement parts, in an non-emergency situation, always check Rock Auto for parts availability and pricing, as PNW VietVet displayed. They usually have what you need, including quality OEM parts, and at competitive prices.

 

[OR VietVet]

I started with something easy so yesterday I added an injector cleaner to the tank and this morning I changed the filter. Keeping my fingers crossed. Before I changed it, I tried starting it and of course, it started right up. This is the first morning in a week that it's done that. Figures.

If that doesn't work, I'll move on to checking the power as Drakon543 suggested. I'm pretty new to working on cars so I'll have to Youtube it to see how to do that.

Thanks for the links, PNW VietVet. I had tried to pick up a relay when I got the filter, but my local parts store didn't have it, so your link will come in handy. And, BTW, thank you for your service.

Make sure, when you check at RA, that the parts I pulled up actually go to your rig. Sometimes the correct RPO code is needed. I think there was a couple choices for the relay but I picked one that SEEMED to be the correct one. Don't assume I looked it up right. Remember: "Measure twice, cut once".

 

[drakon543]

big one there as @PNW VietVet said. if ra just doesn't have access to the actual correct part for a vehicle sometimes it just wont be listed instead of saying out of stock. so with ra always read the part description fully to make sure your buying the correct part. the part images are also generally accurate so you can visually check the part aswell.

 

[liquify33]

*IF* you replace fuel pressure regulator there are 2 types, either is ok. There’s one with a nipple to connect to a vacuum line and one without. It confused the heck outta me when I did mine.

 

[99TahoeOwner]

*IF* you replace fuel pressure regulator there are 2 types, either is ok. There’s one with a nipple to connect to a vacuum line and one without. It confused the heck outta me when I did mine.

Good to know. I saw a video of the one with a nipple but no line was connected to it. I thought that was odd. But I guess it doesn't matter?

How long did it take you to do it?