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starting problem

M

MA87K5

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Apr 6, 2000
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Chicopee, Ma 01020
Was driving and then the jimmy stalled and would not start. Towed it home. Tried to start and nothing. Turn the key and can hear the fuel pump. Checked spark at # 1 plug and have spark. checked fuel line where the pressure guage would connect and fuels spurts out when the key is turned on. Sprayed starting fluid into the intake and it starts and runs til fluid is gone. Could a bad ingnition switch be the reason? Thanks for the help. 2000 jimmy 4.3
 
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UPDATE
I checked the voltage going to the injectors and have 12v while starting. The resistance at the injectors are 12.4-12.6 ohms. I disconnected the fuel line at the intake and turned the key and have flow. I used a spark checking tool and have spark. Some how the injectors aren't fireing. (I hope) Can anybody help.
 
My best advice would be to plug in a scanner and see if you're getting an RPM signal to the computer. Otherwise, you may have a bad ignition module or poor connection at the dist. Without speed RPM to comp, you get no injection. Still seems odd that you have spark and inj don't fire. You checked all the fuses, right? Sorry I'm not more help, it's been a long time since cars were my living. It's hard to get out of my big diesel manner of thinking.
You might consider asking this question in the injection section. This section doesn't get much traffic, and somebody might have more insight over there.
 
I only have a scanner for the codes. No codes came up. I talked to a mech and he said that they went through at least 3 new pumps before they had a good one. I'm going to buy a fuel pressure kit tomorrow and check fuel pump pressure.
 
A noid light will tell you if you have inj pulse, but I don't expect you do if it's not at least nearly starting. You already had some pressure, but finding out how much IS a good idea.
 
he has a 4.3 right? so that would mean he has the internal spyder injection so a noid light would be useless
 
besides that the top 2 reasons those trucks dont start is the fuel pump, and distributor cap, ive also replaced my fair share of coils on those trucks as well, but that wouldnt be the culprit in this case since he has spark, so my bet is on the fuel pump or a clog filter but thats just a bet I cant get all the info i need to know.
 
Then where was he testing for 12v to the injectors? That 4.3 is newer than I have worked on. You could be right, even though he has fuel pressure, maybe it's just not enough. And if he already checked resistance at the injectors, wouldn't he check for a pulse there?
 
by the way these fuel injection systems are picky, so when u do get the fuel gauge, make sure it has enough fuel pressure i would say 55-60 is good(dont know for sure off hand though i can look it up at work if u need me too) and make sure it doesnt leak back down right away, because some of the chevy fuel pumps had a problem with there regulators( i believe yours is in the plenum though) leaking down. also if it is the fuel pump, some of the manfacuturers of aftermarket pumps have gone with a new style pigtail, because they had problems with the old square style(more so on the bigger trucks) but the new one is more rectangular this would be wise to look into if you end up replacing the fuel pump. also the pressure should shoot right up.
 
yes he would check for a pulse there but on the opposite plug the one that doesnt go into the plenum, but it is also hard to do by yourself why everything else he has done he can do by himself.
 
Found the problem. Bad pump. Reads 40 psi before the filter. Good thing is that it came with a 1 year warranty.
 
we use carquest pumps, they have the new style pigtail (if the old style was a problem to begin with), we dont have any problems 95% of the time with them and they dont have any problems warrantying their stuff. replace the fuel filter too.
 
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