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Discussion Starter #1
alright, so just a little background, buddy bought this '91 S10 4.3L TBI and drove it for a few months before it blew a head gasket. I have changed a few of these on this particular motor in the past, so I offered just to buy the truck and I'd change it myself. Well two weeks into what was supposed to be a 2 day job, and here I am ready to just roll it off a cliff. I've finished with the complete gasket job, but now I'm running into a no start issue. The biggest things I've seen so far is that every time I crank the engine for longer than 30 seconds the smaller ground strap off the battery to the radiator core support starts smoking. I double checked the ground strap from the block to firewall and replaced the ground strap from battery to intake manifold. These are the only ones I know of on this model of truck. I verified with a spark tester that I am getting spark to the plug. I do notice that the engine is chugging pretty hard while trying to start, seems like it's struggling. I've also seen the injectors fire fuel sometimes while cranking, but not every time. Truck won't run even with gas in the TBI. I am getting energy to the fuel pump and relay. I'll list new parts below just to give you an idea of what all has been changed, and I'm sure I've left out some details on the troubleshooting I've done, but any help is appreciated. Thanks.

New Parts;
Distributor/ICM
Plug Wires
Plugs
Ignition Coil
Thermostat
Battery
Battery (-) Cable
Alternator
 

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Discussion Starter #2
update; got it running, sort of. it fires up for about two seconds and then dies off on me. i’ve adjusted the distributor cap pretty much all over the place. if i try starting more than 2 or 3 times i’m getting smoke from what i think is the headers. real light and wispy.
 

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I would make sure you have all the senders plugged in. Sounds like You arent getting PCM signal to the pump,but its probably because of a ground off.
 

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Discussion Starter #5
I would make sure you have all the senders plugged in. Sounds like You arent getting PCM signal to the pump,but its probably because of a ground off.
If it wasn’t getting PCM signal the injectors wouldn’t fire would they ? I’ve tried just about everything i can think of but i’m still stuck with the truck starting for at most a minute and then slowly killing itself out. Even while it’s running it still sounds pretty bad, and still having the issue of smoke if i try it more than a couple times.
 

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If the little ground wire is smoking, it seems like you're trying to pass too much current through that wire... so that makes me think you may have a poor connection at the intake manifold where your main ground cable is connected. All of this could result in too little voltage for electronics to work properly. It would be interesting to do a voltage drop test between the negative battery terminal and a clean, solid ground point on the engine. It would be nice to see 0.5 volts or less. If you've never done a voltage drop test, it works like this: put the negative lead of your voltmeter on the negative battery terminal and the positive lead on the engine block. Then have someone crank the engine and see how many volts are displayed. Less is better - it is showing how many volts you are losing through the cable and connections. You're measuring resistance under actual operating conditions - measuring resistance with an ohm meter would be a waste of time in this situation! Voltage drop testing is great for many other applications too. In fact, you didn't mention any ground connection to the frame.... I think some fuel pumps are grounded to the frame, so if you don't have your frame properly grounded, well you can imagine the results!
 
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