steve v

Okay, I've read all through the archives but still have a question. By the way, it's a '98 astro 4.3L V6 2WD with over 220,000 miles on it. It runs absolutely A1 and gets good mileage. However, now it simply won't start.

Here are the symptoms and what I've done so far...

Cranks VERY strong but will not start
You can hear the fuel pump purr in the gas tank when the key is turned
I relieved fuel pressure at the shrader valve and changed the fuel filter.
Tried cranking again, no start. Re opened the shrader valve and gas shot out, so I think the pump is working well.
Removed and examined distributor cap and rotor, cleaned contacts and dried well. Checked for spark by removing the coil wire from distributor and cranking engine. Lots of good strong spark. Engine still won't start.
Checked air filter, which was very dirty. Removed it, closed the filter compartment back up and tried cranking. Same result. Cranked with filter compartment opened up, same result.
Compared ohm readings at ignition coil with those on my '01 silverado (exact same ignition coil incl. part number). Same readings on both vehicles, and my truck starts and runs perfectly.
I went out after dark and tried cranking to look for electrical arcing. There was none at all, so the wires seem to be in good shape.
So that's about it so far. I've read that the fuel pump can be working, but not putting out enough pressure. I re-opened the shrader valve yet again and gas squirted out pretty strongly. To me, this would seem to indicate good pressure. Does this seem right to you?
I'm baffled because the van runs absolutely tip-top. No noises, stuttering, power loss, etc. It just won't start. By the way, it's been damp and drizzly here for several days as well.
Thanks in advance for any help you can give.

ihatemybike

My first thought from my personal experience is a weak fuel pump. Hook a gauge to that valve and see what it reads.

steve v

Started!
Okay, after going through all the other stuff I mentioned, I was still not convinced of a faulty fuel pump. A friend mentioned that maybe the computer was malfunctioning due to the dampness in the air. It was worth a shot, so I looked at the PCM (Powertrain Control Module) next to the battery. I saw a noticeable gap between the two halves of the plastic casing. I then took an electric hair dryer and blow dried the outside of the PCM box for a couple of minutes. When I got back in the van, it started and ran. I then put electrical tape over the gap between the two halves of the PCM to temporarily keep out more moisture.
It rained all night, but the van started again this morning no problem. Maybe this will help others with a similar problem.

ihatemybike

Well that's a new one. Thanks for the update.