Ok, I need some help here! My 1996 S10 Blazer 4X4 will not get running on its own. I can get it started with starter fluid, and it will continue to run all day. But if I let it sit for about 15 minutes or so, it won't start back up on its own. I have checked the battery, alt, Ign Control Mod, Ign Coil, changed plug wires, fuel filter, and fuel pump. I have also just recently changed the fuel tank vent valve (which I broke lowering the tank >0..). Now the fuel pump won't prime, and the fuel gauge is reading full (and I only have about 5-6 gallons in it). When all this started, the truck just died when I was coming to a stop at a stop sign. I'm thinking to recheck the electrical connectors at the pump, but i'm at a loss otherwise. If anyone has encountered this before, please give me some guidance! I'm pulling my freaking hair out on this one!! Thanks in advance.


-Doc

 

You've said you checked the fuel pump but does it hold pressure in the line? If it starts with starter fluid (easy on using too much of that btw) then I'd say it's not electrical but a fuel delivery issue. Maybe a vacuum line is buggered up. Test by spraying brake cleaner over the lines, it the engine revs up then you know that line has a break in it.

 

I have changed out the fuel pressure regulator (forgot to add that), and I know I am getting good pressure all the way up to the block (or at least the spider). Any idea which vacuum lines I should start with, or just start pingin' away at them? I say electrical, cause the pump was priming, and gauge reading fine until I put the tank back up, so I think I may have missed something (it was cold, and I was running out of day light). I'm going to check my connectors tomorrow after work, and if I at least get that working again, I will start looking at the vacuum lines. Thank you for your input, every idea helps!!

I forgot to mention this about the problem! The truck won't start at all. It will turn over, but will not fire on it's own. Would the clogged vacuum line/s cause that too? I would figure that the engine would fire, then choke out, but like I said this thing has got me all confused. Thanks again!

 

pull a plug, hook it back up to the wire & ground it out, have someone turn it over & see if it sparks... as for the vacuum lines I'd just start a methodical way of testing them, maybe mark the ones you've checked by putting some tape on them?!

 

I'll give it a shot. Thanks.

 

Alright! Truck is fixed... I took it to a local shop, and they diagnosed it as the fuel pump. They changed the fuel pump, and now it runs like a top. I got a fuel pump from the junk yard (father-in-law insisted, I protested) and it turns out that one was faulty. It was priming, but it was not providing enough pressure to maintain the 60-65 psi for start up. When I was using starter fluid, I was priming the engine with "fuel" and the pump continued to cycle afterwards. Lesson learned? DON'T BUY STUFF THIS CRITICAL FROM A JUNK YARD! Thanks for the input.

-Doc