S-10 Blazer Cranks but Won't Start

[Chevy Maros]

Hi, I have a 94 S-10 Blazer 4x4 4.3L W motor. I have done a lot of work to this money pit and it has another problem now that I'm having trouble shaking down. Last winter around March of 07 I think, shortly after I fixed its last problem (leaky [COLOR=blue! important]oil [COLOR=blue! important]cooler[/color] lines, btw what a pain in the A ) and got some good running time from it for a change; it just began stalling repeatedly, I ran out of money to commit to the thing so it has sat since and now thats its warmed up I'm back at it but now it won't start at all. I've tried a few things but have not been able to figure out what is causing it not to start. Battery has been desulfated and fully recharged, and [COLOR=blue! important]fuel [/color][COLOR=blue! important]pressure[/color] is at about 62 and slowly leaks down. I pulled plugs and found no problems. I suspect it may be distributor related, I did pull the cap off and clean off the contacts but I'm probaly going to pick up a new cap and rotor (though I'm not sure how to remove the rotor) along with some fresh plugs and perhaps an in-line spark tester tool tomorrow. I would greatly appreciate any advise you guys have.

I have replace the spider injector, feeder and return lines which were leaking inside the manifold, the EGR valve, entire fuel lines and filter, fuel tank and sending unit, plugs and wires all about 1 1/2 - 2 years ago along with many other unrelated parts. Thanks[/color]

[Gabe25]

Do you have spark and the spark plugs? If no spark at plugs, Then start with your coil for spark, then end of you coil wire. If spark is present and no spark at plugs. Check your rotor. Post back your findings.

[LAN2UNOW]

I had to do quite a bit on my 98, the fuel pump did have to go but there was also several issues with the MAF and the Air Charge sensors up on the air intake. Not sure if the 94's have all this the same way as the engines appear to have radically changed around 97-98, but worth an inspection as well. The MAF wasn't causing a no-start, the air charge was feeding a reading to the main CPU that was confusing it and causing it to starve the fuel system.

Fixed those, but still got to the same point - crank forever, no spit or start.

Eventually replaced the fuel pump as it was overheating after 15 minutes and simply dying out, but along the troubleshooting path we discovered a little-know (or realized) sensor for the Oil Pressure/Fuel Pump. This little bugger hiding up on top of the block but in the back somewhere under things apparently feeds the oil pressure guage, but also has a cutoff feature that will stop the fuel pump cold if it thinks the oil pressure's not within limits to prevent dumping fuel into an exploding or seizing block.

Ours wasn't 'faulty' when you read the guages, but it WAS faulty in general and was causing the fuel pump to simply shut down. We traced the entire 12v wire (allegedly usually grey) through the fuel pump relay and other points before we found this little bugger and got it replaced (cheap part, hell to take out and replace in tight quarters). Solved that problem!

Like I said, worth an inspection!

[Chevy Maros]

Originally Posted by LAN2UNOW

I had to do quite a bit on my 98, the fuel pump did have to go but there was also several issues with the MAF and the Air Charge sensors up on the air intake. Not sure if the 94's have all this the same way as the engines appear to have radically changed around 97-98, but worth an inspection as well. The MAF wasn't causing a no-start, the air charge was feeding a reading to the main CPU that was confusing it and causing it to starve the fuel system.

I believe mine has a Manifold Absolute Pressure sensor instead, I'm going to pick up a In-line spark tester and check to make sure i'm getting spark at all the plugs and go from there, got get online which will take some time seeing that I was unable to find one today at four separate stores. Thanks guys.

[dcode]

Got a 92 s10 4.3 cranks but won't start, tried fuel pump fuses they looked ok, tried adding fuel to throttle body and still nothing, new tank and pump last fall, will check for spark but I am alone and do not want to fowl computer with a bad grnd, any suggestions would be appreciated.

[Gabe25]

Originally Posted by dcode

Got a 92 s10 4.3 cranks but won't start, tried fuel pump fuses they looked ok, tried adding fuel to throttle body and still nothing, new tank and pump last fall, will check for spark but I am alone and do not want to fowl computer with a bad grnd, any suggestions would be appreciated.

Welcome dcode to AF. You need to start your own thread if you need help.

[Chevy Maros]

So I got a In-line spark checker tool and tried it on the coil to start with and it got nothing, so I'm going to pick up a coil in the next day or two. I tested the tool on my 93 Camaro and it lit right up so the tool definitly works. It wouldn't be anything else would it? I mean if it cranks but has no continuity at the coil. Thanks

[chazmanjr1]

hey try getting the ignition module checked.

[Gabe25]

If you have good spark to the plugs, then you should take a look at your fuel pressure. You should have at lease 60 to 65psi with the ignition in the on position, then check the leak down. It should'nt drop below 55psi after 3 minutes. If it drops below 55psi. You mite want to check the nut kit or your injector spider for fuel leak. Post back your findings.

[JimmyRiggin']

Originally Posted by LAN2UNOW

I had to do quite a bit on my 98, the fuel pump did have to go but there was also several issues with the MAF and the Air Charge sensors up on the air intake. Not sure if the 94's have all this the same way as the engines appear to have radically changed around 97-98, but worth an inspection as well. The MAF wasn't causing a no-start, the air charge was feeding a reading to the main CPU that was confusing it and causing it to starve the fuel system.

Fixed those, but still got to the same point - crank forever, no spit or start.

Eventually replaced the fuel pump as it was overheating after 15 minutes and simply dying out, but along the troubleshooting path we discovered a little-know (or realized) sensor for the Oil Pressure/Fuel Pump. This little bugger hiding up on top of the block but in the back somewhere under things apparently feeds the oil pressure guage, but also has a cutoff feature that will stop the fuel pump cold if it thinks the oil pressure's not within limits to prevent dumping fuel into an exploding or seizing block.

Ours wasn't 'faulty' when you read the guages, but it WAS faulty in general and was causing the fuel pump to simply shut down. We traced the entire 12v wire (allegedly usually grey) through the fuel pump relay and other points before we found this little bugger and got it replaced (cheap part, hell to take out and replace in tight quarters). Solved that problem!

Like I said, worth an inspection!

NICE TIP!this oil pressure/fuel pump sensor sounds like exactly what has been malfunctioning on my jimmy. It seems like whenever it will die, my oil pressure gauge will also drop really low, then it's like fuel delivery is just cut right off. Thanks for the info, I will look into this for sure.

[Chevy Maros]

Awsome news, got it running today! After a new Ignition Control Module and distributor cap its running great. Thank you to everyone who posted tips and advise.

[Gabe25]

Originally Posted by Chevy Maros

Awsome news, got it running today! After a new Ignition Control Module and distributor cap its running great. Thank you to everyone who posted tips and advise.

Your welcome,. Glad it hear that you found the trouble. Have a great Weekend...............