BIGTEXTRUCKER

New member here and looking for any input out there... Over the past two years (coming on year 3 now), I've gotten to know my 96 Astro Cargo Van really well. My wife bought it for me as a Christmas present back in 2015 which it had a "crank but no start" issue. The last time it was on the road was in 2009.

Once I got the astro home I installed a new battery and changing the oil first. It would kick over with some starting fluid sprayed in and the engine sounded good for the few seconds it ran. So at least I'm not dealing with a blown motor. During my new venture, I ran into a problem when I connected my OBDII Reader to retrieve any codes but it could not communicate to the ECM. The fuel pump did not kick on and no fuel pressure was present. So I started at the fuel pump for the fuel delivery problem.

After removing the tank to inspect the pump and inside the tank, the positive lead wire was melted. I was surprised the tank didn't go "Boom!" lol So after installing a new fuel pump and filter, I had the fuel pressure but still no start. This led me to the spider injector injectors were bad (since it's been sitting for 6 years). After ordering a referb one off Ebay (Oh Yah, bad choice finding out later) I installed it and still no start.

So with the issue of no communication to the ECM using my OBDII, my assumption was a bad ECM. Also just to note that when the ignition was turned on, the digital mileage indicator would sloooowly glow from dim to bright blue

. I ordered a new ECM from Oriellys but it would need to be programmed at my local chevy dealership. One good sign though, after installing the new ECM it tried so hard to start, but of course it couldn't due to the ECM not being programmed yet.
With AAA to the rescue (highly recommend having AAA membership. Saved alot of $$$ from towing my van) they brought my Astro to the chevy dealer. The service tech did fix the communication issue for the OBDII connector. (He pretty much had to so he could program the ECM.) After the programming took, the Astro came back to life! Well, sort of... The technician said it was running rough and needed a new MAP (Manifold Absolute Pressure) Sensor per his diagnostic code it was showing. So I purchased a new MAP Sensor a day prior and my friend drove me to the dealership to pay my bill then drive the van home. I installed the new MAP Sensor and I assumed it ran better than it did, but still it ran rough and very hesitant when pressing on the gas pedal. I'd say it was a interesting drive home with it bucking, backfiring, stalling and coasting at times. I guess someone up above was making sure I got home ok.

So over the last 2 years, error codes have been shooting out the wah-zoo! Some even multiple times after the sensor/part has been replaced. I swear a gremlin or two are nesting in the engine compartment somewhere! lol So here is the rundown of all that I replaced since working on my Astro.

ECM (Main Computer)
MAF (Mass Air Flow) sensor
IAT (Intake Air Temperature) sensor
MAP (Manifold Absolute Pressure) sensor
TPS (Throttle Position Sensor) (Been replaced Twice. The first one from Ebay was bad)
Air Flow Position Sensor
ICM (Ignition Control Module)
Coil
AC Delco Distributor Assembly with cap, rotor and crankshaft position sensor (Old distributor gear was warn down and had up/down shaft play)
New AC Delco spark plugs (the $7.00 ones each, not the cheap $2.00 plugs)
New 8mm Duralast Gold spark plug wires.
New Crankshaft Position Sensor and New Pigtail Connector
New O2 sensors (2 - heated, 2- non heated)
New ABS speed sensors installed on Front Driver & Passenger side wheels.
New Alternator
New Brake Shoes on rear axle
New transmission speed sensor
New Transmission filter and fluid added
Serviced the Rear Differential w/ fresh gear lube
Flushed cooling system and added new DEX-COOL pre-mixed 50/50 (new upper and lower radiator hoses)
New timing chain set & cover
New Water Pump (since not knowing how old the other W/P was)
EGR Valve
Upgraded Spider Injector from CPI to MPI
And recently replaced the intake manifold gaskets with a new plenum cover and gaskets.

As of now, it will idle smooth (hours on end) with no issues until you press on the throttle it will stutter/hesitate at low rpm, but when it gets past say 1700rpm it runs great until 3200rpm and it acts like its governed not revving any higher. Then it spits and sputters again. I dont believe these Astros has a set rev limiter that I know of...

I feel I'm so close to solving this, but stuck at this head scratching issue. I'd like to get this Astro inspected and registered so I can get this puppy out on the road.

The last thing I can attempt is to check the wires from the TPS plug to the ECM plug making sure there is no break in the wires. Mabe I could have another bad TPS? or a bad ECM causing the issues since I fix one thing, then another P0 code pops up, fix that then another P0 code, then the issue I fixed earlier will pop up again...

I know this was a looooong post, but wanted to give some background on what is going on here and all that has been replaced. Your idea/ thoughts would be appreciated. Thanks in advance! 👍

Jim