David99

i have a 99 suburban wont start. i have fuel and spark what next please help.

dmaddox

Can anyone tell us more on the 5 volt problem? I am curently tring to troubleshoot the same problem on my 02 suburban

dmaddox

OK figured it out the 5V problem is that there is two connections on the fuel pump. One of the grey wires is the 12v power for the pump the other is a 5v connection coming from the computer for a fuel presure sensor or something>

Brody mace

Hey guys I have a 99 suburban. I found out some info on this vortech 5.7motor. I've worked on Chevy's my hole life an I've learned something new each day about them. Here's something y'all should check if ur having electric problems to pump or anything. Bc these years an new all controlled by the volts. Some have this an some modles don't. There's an littelfuse 175 mega, on the fan shurowe right beside ur battery. The main power wire from the alternator an the wire that runs on top of the shurowe to the driver side BK of the fuse box are hooked on the mega fuse on one side together. Then the other side of the mega fuse runs to the +side of the battery. Now someone might of done away with the mega fuse an even with a new battery it'll crank all day an never start. But u hook jumper cables to it an to another car and she fires right up. What's happening is if the mega fuse is bad or done away with then the electric circuit is closed off an there is no power going to the motor. Took me a long time to figure this one out bc when I got my suburban someone done away with the mega fuse an I had no idea that they even came out with it. You can Google it. Mega 175 littelfuse. I'd say most of everyone electric (volts) power problems is this right here. I hope this help least of of yall out. Also my suburban was burning up the fule pumps with in prby a month give or take. So eBay 28$ it beat burning up a new pump from parts store that costs 260$ in my neck of the woods.

Paul David

So I have a 97 Tahoe 5.7. Fuel gauge stopped working(reading over full). Truck ran fine for a month until I could get a new sending unit installed. I was driving and truck was hesitating. Parked it when I got where I was going and now it will start(pump kicks on to prime then goes off), but only runs about 5 seconds then seems to run out of fuel. The tank is at about 3/4 full of new gas. I changed the filter because the truck had sat a bit. When I check the test port on the lines up by the engine I don’t get much fuel spray like I’d expect and when I use a simple tester(light type) on the ground at the tank, it seems like the light is dimmer then it should be. Cleaned it up. Still same problem. Relay is good. My next steps are going to be running a ground from the battery and see if that makes a difference and then dropping the tank and putting in a new pump assembly. No codes, check engine light. Just seems to run out of fuel. Spray throttle body cleaner and it stays running. Also changed the mass air flow sensor. Am I on the right track? Anything I’m missing?