Engine will not start

I ran live data today, and the coolant sensor is maybe off one degree from outside temperature I pulled the Idle air and looked inside, there was a little carbon inside not bad but I cleaned it up as best I could hit the key something sputter and no start, this is a tough one.

Okay, I do not think I can do that, this system has the long tube between the throttle body and air cleaner. Keep in mind that the mass air flow sensor and air temperature sensor is mounted on this tube. I have tried these two methods to get fuel into the throttle body, one, sprayed the starting fluid in the tube from the air cleaner side, then tried to start and two had someone try to start it at the same time I sprayed the fluid. There was no change at all not even a little and so I stopped that, I figured why flood it, strange though I pulled the plugs a couple days after that and they looked pretty clean smelled a little of gas but clean enough to run the motor so I put them back in.
I am ruining the starter it will not last much longer, think about it I have been trying to get this running for five weeks now. The battery has been recharged over ten times keeps cranking.
I got a lot of wrench turning time under my belt and I think I have exhausted just about everything I can do on the street with out throwing more parts at it on a guess, it will have to go on a scope.
Unless you can think of anything else to check, look over this post and see one more time.

Try and pull the upper intake off and see if the injector is leaking. If it is leaking then the area will be clean from the fuel washing it down the intake.

Thanks for the reply Chevyforlife.
If you look back on this post you will see the fuel injection spider was tested. I know that this motor is famous for the fuel injection spider so with that in mind I checked it for the leak down test. It held 56 psi for over fifteen minutes. And while cranking the motor it maintained over 60 psi. That would indicate that the fuel injection spider is not leaking. Another indication is that the spark plugs were not soaked with gas.
If this turns out to be the fuel injection spider it would not be because of a leak it would be an electrical issue with it. Remember back on this post that it is also getting good injector pulse to all cylinders as well.

I have followed this post because I had the exact same thing happen with my 2000 Astro. In the last couple months I have replaced the fuel pump, camshaft sensor, and spark plugs. Plug wires and distributor cap were replaced about a year ago. After replacing the camshaft sensor and plugs it ran great! Not a problem. About three days later, tried to start it, and would not even fire. Has spark and fuel. Decided to try and clean out all the moister under the distributor cap. (Did this with a hair dryer). Fired right up without hesitation. I sealed up the cap with silicone in hopes to keep the moister out.
So I would say give that a shot if you have not tried it already.

I hear ya' debjen,
I wish that were the problem here. Keep in mind how long my van has been down over a month. I figured there would be people following this post. This happens a lot with the 4.3 liter from 1996 through 2003 and they develop odd thing things as you put the miles on them. This is the same thing that happens with the S-10's and Chevrolet's, GMC's with that 4.3 liter engine. Some of the more common problems are like the coil, distributor and/or cap, coil wire, there is a recall for that; fuel pump, fuel injection spider, misc. Wiring problems like ground wires or connections because the 4.3 L tends to vibrate more then most engines. GM even put an extra counter balance shaft inside the engine. Oh and the poor intake gaskets, that was true with all GM's v style engines in that year range. Plastic gaskets are bad when you mix medals like steel/iron and aluminum. The good thing about these is they are strong runners and get good gas mileage.
There are many posts all over the net about different things with these but what bothers me is that once they find the problem or do not they never follow up to let the rest of us know what it was. That makes us fix it your self people have to take it to the dealer or garage and pay big money to get it fixed.

Ah' I Can tell you a story about a 1992 Astro TBI, My sister’s van, the infamous 4.3 liter.
She brought it to me running terrible, she could not get it to go right, started right up, idled rough, when you put it in gear it would surge, and if you wanted to go anywhere with this you had to put it in low and tachometer it up, but not too much or it would shut off and you would have to back off the gas. I messed around with it a few days checked for codes, did not have any. There has to be something wrong here ECM maybe? So I ran all the check manually with a multi-meter everything checks out. I checked for codes again and they all came up, what! Then I knew want it was, all my tests triggered the ECM, well that is not bad I guess. Still stumped, I disconnected the fuel line at the engine connection hit the key it was getting fuel pressure, so I went to the throttle body and checked the injectors and they were dripping while the engine was running at idle, thinking possible bad fuel injectors. Well you know it is hard to test the fuel pressure on the TBI system so I got some starting fluid and sprayed it in the throttle body while it was running, it smooth right out, fuel pump right? Nope! I replaced the fuel pump anyway but it was a bad fuel line in the tank, rubber hose split just off the fuel pump its self and was misting in the tank.
Nice war story. LOL

I thought the same thing so I did the compression test two weeks ago and I got from 154 through 158 psi no need to go farther there, which rules out the valve system, pistons and timing chain.
Then I read somewhere that these 4.3's eat the gears off the distributor shaft; so I pulled the distributor and did all the checks on it while it was out. There was no side play and little up and down play, thrust washers were fine, the shaft gear had some wear, maybe two or three hundredths just enough to catch your finger nail on not bad. So while I had it out I replaced the cam sensor too with a new one not used. I put it back in; remember this was the same time I had it on TDC and not 180 out.
I know it should run, and that is why I am out here posting this, looking for help, maybe someone has had this similar problem and could direct me to a possible solution. I guess this is better than nothing; I just do not want to go over the same thing over and over, there has to be an answer.
An answer would be something like the distributor gear, something odd.

I seen broken rocker arms before some with the push rods right through them, bent push rods or rockers that the nut worked its way off and what happens is it misses on that cylinder and either pops into the intake or exhaust, sure the motor fights its self I have seen it but usually runs unless it is multiple cylinders. I would look that way if I did not drive this everyday. Remember it ran fine except for cold mornings and we can contribute that to the weak fuel pump "45 psi", with that said I drove it the night before "the engine was fully warmed up" and there was no signs of a engine miss or noise when I shut it off at 8:00 pm with the temperature forty nine degrees out side and rain and the next morning at 7:00 am it was ten degrees and ice patches here and there; it never started again just cranked and cranked with a sputter here and there.
Oh, and another thing the engine cranks over too fast for that better than 160 rpm and that would never happen with the valve(s) closed, the motor would fight its self too much.
It is a thought, but my guess is still electrical related from the crankshaft sensor area maybe the crankshaft reluctor ring to the distributor, everything has been replaced or checked between these points.
But I have no way to check that ring with out pulling the timing cover off to see; so maybe a scope is in order since the motor still cranks over.
If this was old school stuff with points and condenser I would say no way this engine should not run.
I am sure if I put an old HEI "self contained" distributor in it would start and run. But I would have the CEL and it would not pass emissions, do not think I did not think about it. Lol

Had a problem with factory alarm not letting 1997 Pontiac start. Plugged an old crank sensor in and held it by my drill to trick it into thinking the engine was running. Plugged it back on the car and started right up. I know, I am just sharing an odd one from about ten years ago.

Now that is interesting, but there are other things to consider, like fuel and other sensors. That would through all kinds of DTC codes if you could line it up close enough. Now BCM's can be tricky and the aftermarket alarms can cause trouble too.

Look at me. My mind. Throw codes not through.

By the way. Dose anyone know the location of the BCM on this? Maybe there is a bad wire there. Who knows. Signed, Lost. LOL

Well I got it fixed and I wanted to follow up so anyone following this post would know.
It was a lose wire connection as I figured it would be. Everything else checked out and so it had to be but I could not find it, so here is what I did.
On my last post I was down to the BCM or ignition switch and so I ordered a new switch as it could cause the problem that I had and when I came in I went down to the garage and paid my $300.00 bill with them and went over to look where the plug on the ignition switch plugs in on the steering column, it is up under dash above the brake pedal. I checked the connection and pushed it together and figured I would try it. Yep it started right up, Yes! The guy at the garage stood there shaking his head.
Now here is what happens when you have a problem in this circuit as it is part of the security system referred to as “Passlock” it uses the five volt reference like the ignition system. Now as you put the key in the ignition it triggers a five volt reference for the circuit; you can check this voltage on the yellow wire right at the plug on the bottom of the steering column. When you turn the key the voltage will drop to say 4.5 volts the computer uses the drop as a reference to the key being turned on to verify the ignition cylinder has not been popped out, this is done by Hall Effect or the medal tab passing by the magnet in the switch.
Now if there is a problem in this circuit there will be no codes in most cases but you may or may not have a flashing security light in which I did not. You will have spark, fuel and injector pulse for three seconds. So some cases will have: it starts right up and shuts off, mine never started just sputtered. Something else to keep in mind it would not start with starting fluid either because the computer will not set ignition timing just TDC ignition spark. In my case it explained why my spark plugs were not gas soaked or fouled out when I pulled them and the engine seemed like it was out of time. Now after cranking the engine several times over a month I had gas in the oil, small amount that passed through the piston rings. I guess I am lucky I did not ruin the starter motor.
This circuit is used in many gm cars/trucks from 1996 in up.

Glad to see you found the problem. My 1992 also was a connection issue that I missed (the first one hundred times I was in that area). Years ago I learned the hard way about over thinking/assuming my way to a solution and rarely am I stuck on a problem longer than the time it takes for logical diagnostic elimination and common sense to point it out. Just when I think I am better than average, up pops a problem. Congratulations! I like the way you presented the issues and also the solution.