1989 chevy 1500 p/u. 5.7 liter TBI it runs and starts fine for about 30 secs and then quits like you shut the key off. new fuel filter and it holds a constant 13 psi fuel pressure. it has a nice blue spark from the coil to cap and to plug wires. i have changed the thermostat and intake manifold gaskets for they were leaking. and everything is hooked up right. ground wires are hooked to the thermostat housing as well. it sounds like something is just shutting the spark off. tried a new module and then the whole distributor off a running truck with the same response. looking for good ideas or experience with the same problem. thanks and happy holidays
2006-12-17 12:31:20 · 9 answers · asked by Anonymous in Cars & Transportation ➔ Maintenance & Repairs
the fuel pressure on this model is only supposed to be 9- 13 psi it has two injectors in the throttle body
2006-12-17 12:44:34 · update #1
right after it stops spray starting fluid in T.B. than try to start it. if it starts than its most likely the fuel system.
This truck has a oil pressure shut off that turns off the fuel pump after if oil pres. goes low but a timed relay turns fuel pump on on first start up for a few seconds until O.P. is up than O.P. sw, takes over. Check that switch located above oil filter. Or-
The "sock" filter could be plugged in tank on bottom of pump and just enough fuel will seep through plugged filter to keep fuel pres.for a few seconds to start than goes dry until more fuel seeps through .
You could do a fuel flow test to confirm this.
Remove 3/8" [supply line] at T.B and run pump, should be a steady stream,[not interment] to fill a gallon can in no more than 30 seconds.
This is rare but happened to me awhile back.
2006-12-17 13:45:19 · answer #1 · answered by Old man wrench 4 · 0⤊ 0⤋
I'm not sure that 13 PSI is a bad thing for TBI, for normal (good) fuel injection, that would be a problem, though. Also, if it runs fine for 30 seconds, shouldn't it keep running despite the fuel pressure? Sounds like something on a timer circut, that when it shuts off it kills the engine. Maybe choke, or auto enrichment... Think massive vacuum leak and when it comes off enrichment, mixture is too lean to keep running... look for vacuum leaks
2006-12-17 20:49:14 · answer #2 · answered by Steve-o 3 · 0⤊ 0⤋
That year still have a fuel pump? it could be a fuel pump going out. Maybe fuel injectors? Think of what would shut off the flow of fuel.
Tell you what happened to us once. We had a car that would die on us. It has been years ago. Turned that because we let our car use all the gas except enough fumes to get to the station, we let the tank get really, really, really low we had set the stage for any bits of rust, sediment etc. to sink to the bottom and clog the fuel line.
2006-12-17 20:50:01 · answer #3 · answered by raredawn 4 · 0⤊ 0⤋
could be the ignition module acting up.
13 psi does sound low for fuel injector. should be 30-40 psi. if you changed the fuel filter it could be a bad fuel presure regulator or the pump is crapping out.
2006-12-17 20:37:51 · answer #4 · answered by assmouth p 3 · 1⤊ 0⤋
man there alot of dumb people out there. if you dont know what your talking about dont talk! 13 psi is ok for you truck it could be the oil pressure switch there is a switch that will turn off the pump if oil pressure is to low i believe its located on the passenger side fender not above the oil filter as stated above could be the sock filter in the tank being plugged or could be problems with the wires,relay going to the fuel pump keep looking youll find the problem but id start with the oil pressure switch
2006-12-17 22:03:48 · answer #5 · answered by truss 2 · 0⤊ 1⤋
sounds like a fuel pump. it has enough pressure to run for 30 seconds but then the fuel pressure drops below the limit for the injectors to open and it shuts off.
2006-12-17 20:59:14 · answer #6 · answered by fandsproductions 1 · 1⤊ 0⤋
It sounds like the fuel pressure module. You should have around 40 psi. Your fuel pressure isn't sufficient at just 13psi. Or the fuel pump it'self. Get those checked and I'm sure you'll find your problem
2006-12-17 20:36:08 · answer #7 · answered by whtsthislif4 5 · 0⤊ 1⤋
13 PSI too low. The pumps need to be able to hold PSI under load of at least 40 PSI. I don't have the book in front of me but I think your truck runs in the mid 40 PSI range.
2006-12-17 20:41:33 · answer #8 · answered by Anonymous · 0⤊ 1⤋
replace your fuel pump
2006-12-17 21:29:56 · answer #9 · answered by mandy s 2 · 0⤊ 1⤋