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Discussion Starter · #1 ·
Hey all, first time poster.

A few months ago I bought a 2001 S10 with a 4.3 engine in it. Last week, while driving it to work (highway driving), it died.

Tried restarting with minimal success. It started once out of probably 10 attempts, idled for a minute, then died again. Engine cranks fine, just won't start.

Had it towed to my work and started looking into it, and here's what I know so far:

- It's definately a fuel delivery problem. We tore it down to the spider assembly and did a few tests, had tons of fuel pressure to the spider, but nothing coming out.

- I was tempted to change the spider assembly, but decided to listen to my boss who suggested the ECM. Installed the new ECM and tested while apart and fuel had returned.

- Reassambled everything and started the the truck with no problems. Decided to let it run for a bit, and after two minutes, you guessed it, truck died again and will not start.

Tomorrow when I go back to work, I plan on testing my theory to see if I put the old ECM back in if it does the same thing (runs for 2 minutes and dies). If so, I assume resetting the ECM is allowing it to run briefly, but something is causing it to kill fuel.

If anyone has any thoughts, I'm all ears.

Thanks in advance!
 

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Ruff ruff
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Sounds like a place to start. Replace the fuel filter, its half the size of a coke can and underneath on the frame rail near the tank. When they clog you'll get the same symptoms because the clog settles with no pressure.
 

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Discussion Starter · #4 ·
We changed the fuel filter before we disassembled everything.

Fuel pressure was 62 psi during our check. Fuel pump was replaced right before I bought the truck, so I didn't figure I would be lucky enough for this to be the problem :(

Thanks for the replies though!
 

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might try and see if it will run off of starting fluid if it wont check to see if you have spark getting to your plugs if not check the ignition control module pull it off and take it to autozone and have them test it and have them do that 5 or 10 times to make sure it gets hot. if it will run off starting fluid that means you have spark.
 

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might try and see if it will run off of starting fluid if it wont check to see if you have spark getting to your plugs if not check the ignition control module pull it off and take it to autozone and have them test it and have them do that 5 or 10 times to make sure it gets hot. if it will run off starting fluid that means you have spark.
I had the same symptoms in my camaro before, ended up being the ignition module, I would at least give that a shot
 

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Discussion Starter · #7 ·
might try and see if it will run off of starting fluid if it wont check to see if you have spark getting to your plugs if not check the ignition control module pull it off and take it to autozone and have them test it and have them do that 5 or 10 times to make sure it gets hot. if it will run off starting fluid that means you have spark.

As I said, it's definately a fuel delivery problem, not a spark/ignition problem. Engine runs off starting fluid just fine. The problem is that the fuel is getting all the way to the spider assembly, but not coming out of the spider assembly.

I originally considered that maybe the spider assembly is just bad, but changing out the ECM and doing nothing else caused the fuel to magically start being delivered. Reassembled the intake and ran the truck fine for about 2 minutes, then it died with the same exact issue (fuel stopped being delivered from the spider to the engine).

I get the feeling that something is telling the ECM to turn off the fuel, but don't know enough about it to know what or why.

Frustrating as heck so far.

Thanks for all the suggestions though!
 

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I am having the same problem on my 1998 blazer, just started yesterday. I was going to replace the fuel pump but I was wondering if it could be the security system. I just dont know if the security system will just let the truck crank or if it will start and then shut down after a little bit like some other cars.
 

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Discussion Starter · #9 ·
I actually considered a security system, but I don't think mine even has one. Manual windows and locks, so no remote or anything.

At this point, I'm utterly confused. I'd have given up and taken it to a shop if I had the money to do so. Meanwhile, I'm stuck driving my wife's horrible import, and forcing her to beg for rides to work everyday (her work is 15 minutes from our house, mine is over an hour).
 

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yeah the funny thing is I had an issue with my auto locks that morning but I opened and closed my end gate and it seemed to resolve itself. it just cranks and I cant hear the fuel injection engage or anything. I havent gotten right up to the fuel tank to see if I can hear the pump yet though.
 

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Check the harness going to the top of the intake. If the spider has been changed it is a possibility the connector to the injectors isnt seated properly.

That being said, I would also check for 12v on one side of the injectors, the PCM should ground the other side to fire them. You could test the other end of the injector (PCM side) by grounding your testlight to the battery positive post and cranking......

Also since you have a newer truck you have a CKP (crankshaft sensor) on the front of the motor, check it out, it is probably bad......
 
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