Astro Van won't start in or after rain/high humidity

Van has 94K. Check engine light comes and goes.

Started having this problem last year. Van ran great. Parked in driveway. Rain started that night. Rain stopped. Came out, van wouldn’t start. Just cranked. Three days later, van started. Going down road, had intermittent misses. Tried to fix by replacing cap and rotor with Delco brand. Problem continued.

During summer, fewer problems but occasionally van would not start if it had rained.

So, I installed a new Delco fuel pump, new ignition coil, new Delco Cap and rotor, new Delco plugs with dialectric, new wires…Still, same thing when it rains.

Had it scanned several times at Advanced Auto Parts and just read “intermittent misfires.”

Moved to a new house with a garage. After running perfectly, I parked van in garage. During the night it rained. Next morning Van will not start. Let sit for three days and It started.

Finally broke down and took it to a local Chevy dealer and asked them to do a complete check of everything possible concerning codes and sensors after explaining problem. They only did a code scan and charged me $85…exactly what I get for free at Auto Zone or Advanced. They did recommend a new catalytic converter for $$$$ but directed me to a local shop which installed one for $125.

Spent December in Minnesota snow and cold. No problems. Seems that van runs perfectly if temp is below 32 degrees or when no humidity when warmer.

It has been raining about once a week and problem is back. Van is in garage and will start after a few days. I decided to put a ceramic heater near the front under carriage and the van started after a day.

Is there a sensor that could be the culprit? I’m ready to push this thing over a cliff;-)


BTW: I read these interesting posts concerning this ongoing problem with Astro/Safari Vans:

1) Additional codes may not be stored if catalytic converter is bad.

2) “Apparently the vent holes in the distributor base get plugged up so there is no air flow inside the cap. This allows moisture to build up and it is hard to start. Before you install the new cap and rotor, punch out the small screens in the vent holes to allow air to circulate.”

Sounds like a classic case of something being sensitive to moisture. Get yourself a spray bottle filled with clean water. Put the van in a dark area, and start it up. Then while it is running carefully spray the water on different parts of the ignition system. Chances are you will find one area that will start missing and you will see arcing fromm that spot. There is the culprit,
replace it and all should be well.

Had the same problem with my 2001 Astro van, Took about 2 foot of oven safe parchment paper and Wrapped it around the ignition coil (try at your own risk) no more problems.

In 2010, after a few years of trying almost everything…the one thing I never thought about was the ‘Spider’ Fuel Injector assembly. As it turns out, this is what was causing the problem all along. Once I replaced it, I have never had a starting problem since…no matter rain or shine.

Check the net and you will find several articles and tips concerning the ‘Spider’ Fuel Injector.