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astro van wont start after rain

31K views 46 replies 21 participants last post by  TaxiVan 
#1 ·
not sure what happened but was running fine . has 190k on it but has been reliable as ever. just changed fuel pump dist cap and rotor plugs and wires not 6 months ago. it rained hard night before last and went to try to start and nothing. turns over and tries to start. i have noticed it running a little rough like a slight misfire last few weeks. any suggestions would be greatly appreciated
 
#8 ·
Condensation on the coil tower, probably, exacerbated by a loose coil wire. I would clean all your terminals and make sure they are sealed with dielectric grease. When I had this problem spraying the coil down with WD-40 and using a little starting fluid would usually get it going.
 
#10 ·
I had that problem too. When it was damp and the van was cold, it simply wouldn't start. Soon as it dried out it started and ran fine. Mechanic said "I know exactly what's wrong. You have a cracked distributer cap!" The cap looked fine to me, but it must have been bad because the problem went away as soon as I put a new dist cap on.
 
#12 ·
i 2x guyonearth's
i had the about same issue, my was the coil, shorting to the bracket that holds to the top of the intake.

i let the engine warm up (so the water could evaporate) and used a spray bottle of water, to wet down the top end components of the van with the doghouse off.
see my short vids on this



 
#13 ·
went and got another distributor cap and rotor and seems to be fine but it hasnt rained to put it to the test. the parts man said that he knows folks that have to replace the distributor cap every year on these vans said its a bad design problem on the distributor---not sure how true it is but seems to make sense i guess
 
#15 ·
just wondering if the van hasnt moved over night and it wont start after a rain, how much rain do you get to get water up inside the motor cover. do you leave the hood open at night? i am from a low rain area but dont see how it can get that far into the doghouse latteraly without the vehicle moving. am i missing something?
 
#16 ·
resurrection!

hey folks, so i have the same problem as last time. my videos up there, sparky coil, etc, occur again.

ive had 3 caps, 3 rotors, new plugs, wires, and 4 coils on the astro.
best that i could figure, is that the block has a bad ground?
getting my stupid q's out of the way...
-engine block ground, does it ground thru the engine mounts?
where is the OEM ground? i couldnt find anything near to this, i didnt get under the vehicle though.

i replaced the last coils on warranty. (yay keeping reciepts) the plugs (it was due) and the wires (was also due) where prevnt maint.
but the caps, rotor (yes yes, acdelco only), i tried 2 aftermarkets, and then paid in full for the OEM (thats currently on the 'stro now).

so, the coil bots to the intake, on an alum surface. does this ground to the motor? or in the plastic intake, its set and not grounded.
either way, it was my process of elimination that the engine had bad/missing ground from the block to the body, etc.
fig'd that if the block isnt grounded properly, the spark from the coil, thru the wire, to the plug isnt grounding to the electrode on the plug, and causing resistance when its trying to fire. (concur or flame me for being wrong? lol)

when i replaced the coil up at my 'rents house (178 miles from home) when the van wouldnt start for me, this time i added a 10ga grounding wire from the back passenger head a major body ground (both cleaned, prepped, etc) and the van seemed to be 'more happy' and run 'stronger' than it has in the past 2 years. engine had more power, w/ a load (400+lbs of stuff) and a full tank, + runing the a/c. that and i observed crazy +++ in MPG from rents to home.
i observed 13 gal to get 178 miles, then 7 gal to return home, both w/ a/c and the return trip +400lb in weight added.

thoughts?
 
#17 ·
WOW, You may be on to something Matt. I'm still learning a lot, But it sounds as though you have hit it on the head. I'll wait and let others chime in now. Did you grab any pix of it? Thanks, Jim
 
#18 ·
Grounds should be:

LH Radiator Support
RH Radiator Support
LH Cylinder Head
Generator Bracket
Firewall, extreme passenger side of the engine compartment
 
#19 ·
mattsrevenge said:
-engine block ground, does it ground thru the engine mounts?
where is the OEM ground?
Engine ground is next to the crankshaft balancer on the front of the block. Main body ground is on the radiator support in front of the battery. The coil itself does not need to be grounded, but the ICM (module)has a ground that splits at a splice and terminates at the thermostat housing and the left rear of the engine block near the knock sensor.
 
#20 ·
thanks on the ground locations,

the RH firewall (facing the astro, driver side) and the firewall (above the blower motor) ive pulled and cleaned (they where clean, no rust/corrosion), and its the ground above the blower that i wired my pass side head bolt to (it holds one of the wire pack retention clips). i pulled the ground on the drivers side of the head and cleaned those as well (besides covered in oil, metal was clean under the bolt). so that leaves me with the

-LH radiator support
-generator braket (and i bring this one up becuase 4 years ago the van chewed thru 2 alternators in 30 days... i didnt repair that one, before i own, shop did r&r 1st time, and then diff shop did 2x under warranty)
-ICM (module)

ill be checking those later this week/weekend (whenver i FIND time haha)

much thanks everyone :rolling:
 
#21 ·
I have been having this problem for 5 years. Have done all that everyone here suggests. Still, no start problem exists. Replaced crank sensor too.

I think I was on the right track for the crank sensor. But it's not the sensor, it may be the connection. I've seen several posts referring to this as the possible culprit. Take this one for example:

"I think you have a poor electrical connection to the crank position sensor or at the computer end. You can dis-connect the battery and un-plug the sensor and spray it out with WD40 and you can do the same at all the computer plugs."

Meanwhile, I discovered that if I place a 1500 watt small ceramic cube heater just under the motor and just past the air dam and let it run for 3 hours or more, the van will start.

This spring, we have had lots of rain so I have been parking with the nose end just inside my garage. (Garage is loaded with stuff being readied for yard sale.) I run the heater during the night and the van always starts in the morning no matter how bad the rain was or is.

Problem is when I go some where and have to let van sit in humid air or rain.

This past friday, my wife drove van to work and it would not start when she wanted to come home. Went up there and got her. Left van until yesterday hoping it would start. But ended up having AAA tow it home 37 miles.

I immediately placed the heater under the motor and let it run foor about 4 hours. Went out to start van and it started!

Getting back to the sensor, I'm going to see if the connecting wires are shorting and/or if the seal around the connector is bad.

Will let you know.
 
#22 ·
llulua said:
I have been having this problem for 5 years. Have done all that everyone here suggests. Still, no start problem exists. Replaced crank sensor too.

I think I was on the right track for the crank sensor. But it's not the sensor, it may be the connection. I've seen several posts referring to this as the possible culprit. Take this one for example:

"I think you have a poor electrical connection to the crank position sensor or at the computer end. You can dis-connect the battery and un-plug the sensor and spray it out with WD40 and you can do the same at all the computer plugs."

Meanwhile, I discovered that if I place a 1500 watt small ceramic cube heater just under the motor and just past the air dam and let it run for 3 hours or more, the van will start.

This spring, we have had lots of rain so I have been parking with the nose end just inside my garage. (Garage is loaded with stuff being readied for yard sale.) I run the heater during the night and the van always starts in the morning no matter how bad the rain was or is.

Problem is when I go some where and have to let van sit in humid air or rain.

This past friday, my wife drove van to work and it would not start when she wanted to come home. Went up there and got her. Left van until yesterday hoping it would start. But ended up having AAA tow it home 37 miles.

I immediately placed the heater under the motor and let it run foor about 4 hours. Went out to start van and it started!

Getting back to the sensor, I'm going to see if the connecting wires are shorting and/or if the seal around the connector is bad.

Will let you know.
Good info. Welcome to the Forum. And please keep us posted. Jim
 
#23 ·
llulua said:
I have been having this problem for 5 years.
Has it always been a no spark condition when it will not start? Ever store any codes? I'm also wondering if the heater is drying it out or expanding a loose connection. The CKP connector is right there closest to the heater, so maybe? Do you have a digital meter?
 
#26 ·
well i must admit i had to change the distributor gear and the gasket maker was not such a good idea lol. i used to think ppl saying dont get the disributor cap from auto zone were just talking crap BUT NOW I AM A BELIEVER. you can just look and see the craftmanship difference. after the gear and new distributor cap (delco this time) runs better than it has in years---pushin over 200,000 miles and like i said its runnin better than it has in years---just hope it stays that way
 
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