97 sierra 5.7L vortec wont start

[crossfire879]

My 97 5.7L Vortec won't start. It turns over and spits a little trying to start but it won't go. A few months ago it left me stranded on the highway. Got it towed to a chrysler dealership (only one who would take it that day). They replaced the pump and sending unit with NAPA crap. Truck ran good for about 4 hours. Stalled again in the next town so then I got it towed to the Chev dealership there. They replaced the pump and sending unit wth GM parts along with the filter and lines. Ever since then it has a hard time starting in the morning but it would eventually start and now it won't start at all. I poked the schrader valve and fuel squirted out but I'm ont sure how much pressure. Any ideas? It's pretty frustrating when you take your vehicle to two different dealers and neither of them can do a proper repair.
Thanks

 

[Molson02536]

My 97 5.7L Vortec won't start. It turns over and spits a little trying to start but it won't go. A few months ago it left me stranded on the highway. Got it towed to a chrysler dealership (only one who would take it that day). They replaced the pump and sending unit with NAPA crap. Truck ran good for about 4 hours. Stalled again in the next town so then I got it towed to the Chev dealership there. They replaced the pump and sending unit wth GM parts along with the filter and lines. Ever since then it has a hard time starting in the morning but it would eventually start and now it won't start at all. I poked the schrader valve and fuel squirted out but I'm ont sure how much pressure. Any ideas? It's pretty frustrating when you take your vehicle to two different dealers and neither of them can do a proper repair.
Thanks

Your going to need a fuel pressure gauge, and there shout be 62-65 PSI at the shredder valve with the key on engine not running. Once the engine is running, the fuel pressure should drop about 5 PSI. You can try spraying some Carburetor through the throttle body or starter fluid through the intake before the filter. Reason you want to spray before the filter is to ensure there is no back fire in your upper intake manifold, which would cause more issues and big $ to repair.

If the engine starts up, then you have a fuel pressure issue. With you having replace the fuel sending unit not to long ago. inspect the ground wire to your sending unit, a bad ground will cause the Sierra to have low fuel pressure from a weak fuel pump.

Good luck and keep us posted and check to make sure you have a 100% working ignition system also.

 

[webf2010]

What molson instructed is absolutely right, but i does not make any sense in following the above procedure as you have already paid for two times, its better to leave the vehicle in the dealers place and ask them to test the vehicle for two or three days. if nothing works then you may require to solve it in front of the majesty.

 

[crossfire879]

Thanks for the tips guys. I tried to start my truck again today and got nothing. I can hear the pump buzzing and I had power to my relay. So even though it is not a good idea, I dumped a little raw fuel in the throttle body. It hesitated and spit and sputtered as I tried to crank it. Eventually after cranking it and dropping a tiny bit more fuel into it, it finally started. It surged for about 20 secs and stalled. I cranked it again and it started up and now it is idling and running fine. My mom has been driving it the past few months and she is bad for running tanks damn near dry before getting fuel. The morning it wouldn't start was after our first frost of the year so I am thinking that the tank was probably a little too empty and water inside it froze. Any ideas about what could've happened? Like I said raw fuel in the throttle body isn't a good idea but it got it started and now it seems to be running fine.

 

[Molson02536]

Thanks for the tips guys. I tried to start my truck again today and got nothing. I can hear the pump buzzing and I had power to my relay. So even though it is not a good idea, I dumped a little raw fuel in the throttle body. It hesitated and spit and sputtered as I tried to crank it. Eventually after cranking it and dropping a tiny bit more fuel into it, it finally started. It surged for about 20 secs and stalled. I cranked it again and it started up and now it is idling and running fine. My mom has been driving it the past few months and she is bad for running tanks damn near dry before getting fuel. The morning it wouldn't start was after our first frost of the year so I am thinking that the tank was probably a little too empty and water inside it froze. Any ideas about what could've happened? Like I said raw fuel in the throttle body isn't a good idea but it got it started and now it seems to be running fine.

Running it close to empty is a bad thing. More common for any dirty to get picked up buy the sending unit and plug up your fuel filter much sooner. Start with replacing the fuel filter and inspecting the fuel pressure at the shredder valve as mentioned on earlier post, also checking the ground wire for any damages such as corrosion.

Post back on how your doing and be safe. Take not, keep a can of starter fluid or carb cleaner in the Sierra. |Just incase you have a starting issue out on the go.