Chevy & GMC Vans

man, i'm full of mysterious issues this week.. i know

in the 99 when i turn on MAX AC i don't get it through the face vents 70% of the time, it only comes out the dash vent. when i change the setting to floor it comes out there and the dash... when on normal AC same deal.. it only comes out the face vents 30% of the time...

ideas?

thanks againnnnnnnnnn (groaning)

rob

Have you checked the vac lines?

Vac is what controls where the air goes.
It is usually the vac line from the engine to the vac reserve ball down under the heater/A/C box on the co-pilot side under the hood.

Let us know if you need more help.

sorry for my stupidity ... what's the easiest way to find this ball.. from under the van ? obviously, i'm looking for something round? lol

i have really learned to miss the electronic/cable controlled 'everything' my dodge had and dislike the vacuum controlled everything these things have.

On my 90 it is just a bit bigger than a large grapefruit. When looking at a slight angle, less than 1/2 of it can seen, the driver side of the ball.
Your 99 may be different.

A bright light helps since almost everything down there is black.

Anyone else to chime in?

well, I still haven't had the van or the time to check it. Jen gave me an update today saying that it didn't seem to be cooling at all anymore up front. could this mean that the system is simply low and need a recharge?

or are we still on the mysterious vacuum ball thing?

it was 104° F here today with the humidity .. ugh!

i'm probably getting to this one today or tomorrow.

when you say 'check the vac lines' what exactly am i looking for? and am i looking anwhere else other than the grapefruit sized black ball ?

ok.. I found the little hard plastic line that runs from around the firewall area across the top of the motor and broke or ended behind the alternator. then i found the one that comes out of the vacuum ball thingy and runs over to the other one.

i cut the bad brittle parts out and slipped some rubber hose over each end and rerouted the line up and over the wiper motor to keep it away from future heat issues. smooth curves no kinks or harsh bends. no other cracks in the line that i could find.

here's the problem... the piece that runs into darkness of neverland near the firewall also broke.. i can't see where it's supposed to hook up back in there...


umm.. help?

thanks
rob

I wish I could help you. Thankfully I have not had vac problems up to this point.

Oh, have you had your doghouse off lately? The vac lines going to your heat/ac controls can get caught when you put it back on if you are not careful. I was warned about that when I did my tune-up a while back.

Here is a picture from inside the van, not exactly the clearest but it should guide you as to where the hose goes. I'd take a better pic, but the wife took the camera with her this weekend.



It is pretty common for that line to rub through causing the air only to blow from the defrost vents. You can reach from the front, but its tight.

Scott

thanks guys.. and it's true .. a pic does say a thousand words.. lol

looks like i'll have to find that sticky about how to remove the doghouse on a later model van i've never had it off on the 99 and don't know where to start

Getting the dog house off is pretty easy, my '97 should be the same as your '99. I wish I had taken pics when I did it last time, but it was winter and it was cold and I just wanted to get the van running again.

well again.. thanks for the help and especially the pic. found the other piece of broken line at the back of the motor. reconnected with new hose and all is right with the AC once again.

the doghouse removal on the 99 was similar to the 94 with the exception of the fact that you can't take it right out of the van without removing a seat. now that's engineering at it's best.

You can get it out without removing the seats, but its real tight. I just put the seats all the way back, and I think tilting the front down also gives a little more room. And removing the bottom dash panel on the driver side gives more room too.

But it definately is possible with all that stuff in the way, just really tight, rub on the seat cushion tight

Scott

I got the one out of my '97. It is tight, but possible. As mentioned, seats all the way back.

When I said I had not had this happen, I spoke to soon . . . the line broke I went in and found it after I realized that whoever fixed it before me put wire loom around the fix (yeah, like that is going to help). Not only that, they taped both ends so it was a bear to get off resulting in breaking even more line. I think I will eventually just have to replace the whole thing. For now I picked up some tubing at Napa, and once the van cools down, I will hopefully get everything up and running again as we are heading out early this afternoon to go camping and not roast the whole way.