Help diagnosing truck problem

Doc

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I drove my old Silverado 20 miles home and while turning in the driveway it died. I restarted it long enough to back up to the garage, but it would not start after that.
It appeared that we had no fire, so I replaced the coil. It started but died again after driving to the end of the driveway and partway back to the house.

This is on an old Chevy Silverado (1993) w/ 350 engine w/ 190k on it.

Looking for ideas on what to check next.
 
Two quick checks

You sure that the fusible link isn't fused...:D

The other thing to check is that you haven't loss your ground...
 

Doc

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What would be an indication of lost ground? The engine turns over plenty fast. So fast at first I thought the starter was free wheeling. :D
 
What would be an indication of lost ground? The engine turns over plenty fast. So fast at first I thought the starter was free wheeling. :D

I took your no fire statement to be no juice!!

If your starter is turning over forget the ground statement...:rolleyes:

You are on to ignition...as in Houston we have NO ignition...:D

OR
Distributor cap
Coil
Condenser in the distributor
Fuel pressure regulator
Compression
See if the timing chain slipped
Adjust tps sensor
Relay
Spark igniter
Try to bypass the fuel pump to see if it still is working correctly
vacuum leak
change EGR valve
and so on and so forth...:)
 

Doc

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My son had a dohicky (technical term) that you plug in between your spark plug wire and spark plug that shows whether or not the plugs are firing. That is what I meant by no fire. we traced it back to the coil. Juice was good going into the coil but not coming out. So we bought a new coil.
It rained last night so no progress at all ... but tonight I hope to get into the distributor and see what's shaking in there. Hopefully it's just the cap or rotor or something fairly routine & cheap like that.
I need to pull my little boat out of the water so I needs my truck to be running. :pat:
 

Doc

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I would need the truck to take the tractor there, the boat club is 20 miles away.
 

Jim_S

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I would need the truck to take the tractor there, the boat club is 20 miles away.

Now were getting to the root of the problem. Doc doesn't need his truck fixed, he just needs a faster tractor!
 

irwin

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I drove my old Silverado 20 miles home and while turning in the driveway it died. I restarted it long enough to back up to the garage, but it would not start after that.
It appeared that we had no fire, so I replaced the coil. It started but died again after driving to the end of the driveway and partway back to the house.

This is on an old Chevy Silverado (1993) w/ 350 engine w/ 190k on it.

Looking for ideas on what to check next.

Unfortunately there's several components that could cause your symptoms, because it started again and I assume ran ok for a bit I don't think it's the cap, but check the center spring loaded nub.
Let's see:: crank sensor, pick-up coil, ignition module, even the ecu (electronic control module) or as Paul said the fuel pump could be shot, it may be pumping just enough to start up sometimes, then gives up. but you said no spark so most likely it's a ignition or a control issue. None of these parts will set off the MIL except the crank sensor under some conditions.

I don't think it's your coil pack, it usually dies outright (wouldn't start at all)

I'm sure I'm missing something, like a bad ground somewhere, even at the ecu? but these parts are common failures.

Do you have a heavy gas smell? You could pull a plug and see if it's damp with gas. I can't remember if this system has a fuel pressure hook up schrader valve, but if it does and with no start you could depress the valve and if only get a little spurt, that would be a fuel delivery indication. (it should have about 40-60 psi) some of the systems need the whole spec pressure 46psi? (if has truely no spark I'd start somewhere else though)
Gotta recheck spark and fuel delivery to isolate control issues.
I'm sorry I can't be more specific help Doc, but with no CEL (MIL) to guide us?

If you can get more info I might be able to be more help.

Good luck............Tim (who does this for a living)
 

Doc

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Very good suggestions / guesses Irwin. You were right on I think. As long as the ignition coil module and the ECU are the two components on the distributor. We had focused on it being a fuel issue, but after testing didn't think that was it. Scratched our heads some more and went to google. Did a search with lots of key words describing the problem. Someone with the same model truck as ours had this exact problem just a month before we did. Turnned out to be the distributor. We replaced the entire distributor and all is good again. I 'think' we could have replaced the electronic modules on the distibutor and had it fixed, but like the GM master mechanic said, you have no warranty on just the plug and it has been his experience that the distributors are better off when replaced as a whole. Plus you get a warranty. Two of the modules cost 2/3's the cost of the distributor anyway.
Sure missed the truck last week. We had a flood and needed to take two boats out of the water, plus our son's finance's car broke down and we needed to haul it home but couldn't. Sure glad to have the truck back in service. :D
 
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