Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
HelloCustomer the first thing you need to concentrate on, is fuel pressure. You need to check for two things, that pressure is within spec and that pressure holds and does not drift down after you shut the truck off. It is natural for pressure to slowly drift down over a 30 minute period, but not to 0. If it drops quickly it would indicate either a fuel pump or a fuel pressure regulator. This is where you need to start. Fuel pressure has to be 55-62 psi with the engine off and the key on.and should be there immediately when cranking the truck. Immediately after shutting off the truck, it should hold rock solid.
Your JA Expert,
Just one follow up question before I check fuel pressure. Does a low fuel pressure condition also cause the spark plugs not to fire? I may have forgot to include this in my original question but I am getting no spark.
No if you have no spark, you may have a crank sensor related issue. The fuel pump would have no affect on spark, but a faulty crank sensor would cause the injectors not to fire as well. This is where a scan tool becomes a major part of the diagnosis. I am going to send you the complete procedure, schematic and descriptions. Take this info, review it, a fuel pressure test would be good, but I think you are going in a different direction. Review this info, see how comfortable you are pursuing this on your own. Let me know. This is where voltmeters and scopes come in handy for getting info.