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1993 Gmc Jimmy 4.3L Vtech.....not starting


Junky1991
12-10-2005, 11:48 PM
Hate to put another one of these threads on here because there are a few but here it goes. I live in Iowa and it has been cooooooolllldddd lately. Well on tues morning I woke up and it was -18 outside and for some reason my garage door was left open and when I went to start the Jimmy it would not start. To give a background I have changed the coil, plugs, wires, dis cap & rotor already and the battery is ok. Now that same day it did start, I ran it for a couple of min and shut it off and would not re-start. I have checked the coil and plugs and they seem fine. I sprayed some starter fluid in the intake as well as fuel and nothing, not even a puff. When I turn the ignition I hear the pump turn on and it does crank over but nothing. I do not smell any fuel at all, cept when I try the starter fluid. I am getting ticked because Im broke, going to college and already have a 91 plymouth van sitting next to the jimmy needing a fuel pump (that one is going to the junk yard :) so I do not want to think that the Jimmy is going down the same road. And everything I see in the other posts looks like you need to replace everything under the sun to get it working again and like I stated before I'm broke. So with that said...what should I start looking at? It has a full tank of gas and it seems that every vehicle I own breaks down when it has a full tank of gas. Could it be that the lines may have gotten cold? I put in some heet yesterday and still nothing. O and also when I did the tuneup did not replace the filter just in case you ask. Thanks

taylorman
12-11-2005, 09:13 AM
Find a fuel pressure tester and check your fuel pressure. Pressure should be some where between 55 and 60 psi. Also, you might check your fuel relay. If you wait a little longer a fella named rlith will probably help you a bit more. He seems to know a little more than most when it comes to these 4.3l. My 93 had the same problem and it turned out to be poor fuel pressure but you should also check the relay. Hope this helps a little.

Junky1991
12-11-2005, 05:06 PM
Thanks. Will try that out. Im just trying not to get too frustrated with it, my van needs a fuel pump and im just giving up on that one, put too much money in that and dont want to waste anymore. Now when you check the fuel pressure, you just put a guage in the gas line correct??? I know the pressure should be 60-65 psi. Will also check the fuel relay. It seems from my readings that if its poor pressure, most likely is the fuel pump correct??? Also when I was messing with the coil last night my hose to the pvc valve snapped...is this hose something I need to go to a dealer for or should a parts place have it?

MT-2500
12-11-2005, 05:18 PM
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
93 code w 4.3 gm engine should have 55-61 fuel pressure.
Cold start should be close to 60 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 55-61 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.
Post back fuel pressure readings.
MT

MT-2500
12-11-2005, 05:23 PM
Also check for good spark at two or more spark plugs.
And go easy on that started fluid.
MT

Junky1991
12-11-2005, 10:02 PM
Will try that, its finals week so will not be able to mess with it till next week. But will let you know the pressures that I find. Thanks again for the info.

photohawk58
12-12-2005, 07:26 PM
Will try that, its finals week so will not be able to mess with it till next week. But will let you know the pressures that I find. Thanks again for the info.

Hi, I have 93 just sitting most of the time (here in the Northeast) Last week when it got cold, and had only about a half of tank of gas, I think my gas lines froze. With the temps you posted, I hope you were using dry gas all the time. I could be wrong, but after 3 cans of dry gas my vehicle is running just fine. Hope this helps.

Photohawk

scoutout
12-17-2005, 12:08 AM
check for electronic pulse that goes to the injector.
also check rubber lines that mounts to the fuel pump last check hard lines that plug into spider assmb.

Junky1991
12-19-2005, 12:11 AM
Will take a look, since im out of school have more time. Now I dont smell any gas at all up front, just the stuff I sprayed in there. Dont know if I will have access to fuel press. guage, may just take it to a shop since they know more about it than I do. I just dont want to mess anything up.

Junky1991
02-18-2006, 02:15 PM
Sorry for the long time span since last post. It was my distributer that was faulty, I was getting no spark. So I had the shop change that, fuel filter, and a new battery. Now it runs but still bad. The shop said the fuel injectors may be going out. Anyone have something I can try or how hard is it to change out. Thanks for all your help.

MT-2500
02-18-2006, 04:07 PM
It only hads one.
Check your base timming and firing order.
Is it missing on or just running bad?
pull one plug wire ata time and see what it does.
Give us your fuel pressure readings.
Cold start engine running and watch for fast leak down.
MT

Junky1991
02-20-2006, 03:58 PM
It only hads one.
Check your base timming and firing order.
Is it missing on or just running bad?
pull one plug wire ata time and see what it does.
Give us your fuel pressure readings.
Cold start engine running and watch for fast leak down.
MT

Just running bad, not missing or backfiring, it hesitates till bout 20mph then gets power and is fine, idles kinda ruff. I guess I will need to invest in a fuel press. guage. The shop said it may be the spider assembly????. Thanks for the info :)

MT-2500
02-20-2006, 04:42 PM
Also check that egr valve.
MT

Junky1991
02-26-2006, 09:24 PM
Well im still working on that fuel press guage, need money :(. Well I took it for a spin, ran down the fuel to 1/4th of a tank, filled up and has been running fine ever since (knock on wood) no ruff idle or anything, but my abs light is comming on still (issue for another day). Also is it easy to change out the window motor, my drivers side does not come down, it gets hot in IA and I dont want to look like an idiot with 3 of the 4 windows rolled down, plus it would make going to the drive thru alot easier :)

MT-2500
02-26-2006, 09:52 PM
You might check the switch and wiring going threw the door first.
Could just be a power problem.
If you have to change the window motor just keep your fingers out of the road.
They have a bad habit of eating fingers. Some windows regulators are spring loaded so remove the motor with caution.
MT

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