Car Repair > gmc jimmy stalls at idle sometimes it will run great for >

Ask Your Car Question. Car Experts Answer You ASAP.

(Not a Car Question?)

93 gmc jimmy stalls at idle,sometimes it will run great for weeks at a time.doesnt matter if its cold or warm, if i give it a little gas there is no problems. when it does stall it wont start unless i spray car cleaner in the intake.I have replaced the fuel pump,TPS and coil.If i let it set for a few hours it will start right up but die at idle.Fuel pressure is great,no codes as i had a friend at a local garage hook up a computer.when it wont start i still have fire. Please help

Optional Information:
1993 GMC Jimmy 4.3w

Customer (name blocked for privacy)

Status: Closed Value: $10

Greetings! does this have a throttle body? Is there gas being sprayed in the throttle body when cranking when it does not start?

Reply to amedee's Post: no it has the cpi injection or spider injector, it has me very stumped

Greetings!
I would check the fuel pressure regulator. I would do this by turning the key on and wacthing fuel pressure. if it drops than u have a leak somwhere. I believe it is located inside the plenum with the spider injection. It is round, about a quarter size and normally has a vaccum line going to it. but in your case because it is inside the plenum that when running already has vaccum it does not need a vaccum line going to it. If it is leaking gas than it can cause this problem. If so, the diaphram has ruptered and there is gas entering the engine that is not accounted for and the regulator will need to be replaced!

Reply to amedee's Post: Thanks for that, but we have already tried that route, fuel pressure stayed right at target. any other ideas?

THIS ANSWER IS LOCKED!
You can view this answer by clicking here to Register or Login and paying $3.

I am leaning more toward a bad Ecm, i now have the top plenum off and the popet nozzle pulled from the intake, when i turn the engine over i get no fuel from the popets, when i jumper the injector i get fuel

When you jumper the connector, are u giving it power or a ground?

I give it both a power and a ground, i disconnected the plug and ran jumpers to the two pins.

If u get no fuel from the poppets when cranking and there is fuel pressure, u will have have to figure out if u are losing power or a ground. turn the key on and see if there is power. we will go from there let me know.

when i turn the key on i have power,per my test light, with a multimeter i get 11.8 volts at the harness

So u get power at the starter on both terminals when cranking? correct?

At the starter?? no no, both terminals of the injector harness have power, 11.8 volts, thanks for being so patient.

sorry about that got confused. We are talking about the power to the injectors. So we have power, and i am guessing there is no signal to the injectors when cranking? is the check engine light on key engine off? And is there spark when cranking?

Think you can answer this question?
Login or Become an Expert

DISCLAIMER: You acknowledge that any information you may obtain from individuals you contact through use of the Just Answer service comes from those individuals, not from Just Answer!, and that Just Answer is not in any way responsible for any of the information these third parties may supply. The site and services are provided "as is" with no warranty and no representations are made regarding the qualification of an Expert. Responses and comments on Just Answer! are for general information and are not intended to substitute for informed professional advice (such as medical, legal, investment or accounting) and do not establish a professional-client relationship. Just Answer! is not intended or designed to address EMERGENCY QUESTIONS which should be directed immediately by telephone or in-person to qualified professionals. Please carefully read the Terms of Service.

Just Answer! > Car Repair

Related Answers