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Spark and Fuel, and that's about all you need. It occurs to me that you should check the vacuum lines again. I have had the MAP sensor go bad and it actually ran better after I unplugged it. With the map sensor disconnected it will go into linp=in mode, but that's better than nothing.
It kind of sounds like a vacuum problem and the MAP sensor is "a priority circuit": so that's why the vacuum needs to be checked again. Fluttering the gas pedal is a clue.
Sometimes a vacuum leak is only obvious after very careful checking. It is hard to imagine what is wrong, but working on the Chevy will only get the S-10 working, unless you are lucky enough to have some litte magic elves work on it while you are sleeping, but that only happens in fairy tales.
NAJ has a good, systematic approach. I have never had to check fuel pressure myself, it either works or it doesn't in most cases. It is good to check the fuel pump electric connector/plug at the gas tank because sometimes they are loose and charred by the resistance. Some people conjecture that the long distance wiring run can cause a voltage drop that can affect the pump. It is probably something simple, but it will only seem that way after you fix it. Good luck.
 

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Is there anything in the fuel injection that would cause this? Been busy working on my S10.
If you mean with the injector itself, probably not, unless you see something obvious that may be causing your intermittent "shuts down" condition this will require diagnostics on your part.

SEE POST 18.
 

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You also need to verify all controller ground circuits have continuity to ground, < 5 ohms.
Be absolutely 100% sure both Battery Terminals/Cables are Clean and Tight, cannot move them by hand.
Be sure the main controller ground is securely attached to the manifold and firewall.
Be sure the ground wire from the R/S engine mount to the body is secure.
Be sure all pigtails from the - battery terminal are securely connected to ground.
I do not know exactly where the main controller ground is connected on a 94 TBI, here is a pic of my car, yours should be in the same general area.
Motor vehicle Vehicle Automotive design Car Automotive air manifold


The wiring states..."Ground E, Throttle Body, Right Side Of Manifold."

To eliminate any obvious problems, start the car and perform a wiggle test on the wiring/connectors for the ASD Relay, All Sensors, HEP and Coil Connections.
You may also want to spray all connections and the ignition wires with water to look for arcing to ground.



I do not think this is a MAP Sensor issue since no Code 13 or 14 was set in memory.
All of the MAP Sensors I have seen fail (and there were a lot) were on low Pressure TBI cars and they ALL resulted in a NO START CONDITION, every vehicle was towed in with fuel fouled plugs, fuel diluted oil. It got to the point that when they were towed in we went out with a new MAP Sensor, plugged it in and started the car, drove it in to the shop and then called the leasing company for authorization for diagnostics, there were so many that after a while the leasing company just said "Another Map Sensor Issue...?", we said "Yes, with a chuckle" and they said "OK, 1/2 hour diagnostic time, replace the MAP, Plugs, O2 Sensor and Change The Oil."

If you want to check MAP Sensor Calibration again, you will need to connect a digital voltmeter and vacuum/pressure gauge inline with the MAP vacuum source. and go for a ride.
What was MAP voltage reading when the problem happened?
What was vacuum reading?

The funny thing is it probably took longer for me to write this than it would have to check all of this.
 

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I had a MAP sensor fail that did exactly that once in 1995 in my 84 Daytona (once replaced, resolved the issue), and not on a Mopar, but had a fuel filter absolutely collapse inside on a Toyota Truck w/ a 22R engine, that uses the same exact numbered Fram canister filter as My Daytona has on it.

I was so sure there was no possible way it could be that bad, so I cut open the filter can after I replaced it and the issue immediately went away, and the usually oh 4" long by 3" element inside the can was collapsed down to about 2" cubed and looked like a small hourglass shape, and so tight & nothing was getting through that super tight sponge....No light, and certainly no liquid, like fuel in massive decent quantities at least. Also check every ground strap, and there are many.
 
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