Truck in sig....


Anyway, here is what is happening. From the day I bought the truck...the heater button has never worked...I push it and everything shuts down. I didn't think much of it since I put it on VENT then I get heat.

The PO had the truck revamped over to R134 and replaced all the parts to the tune of about $900 bucks...and it worked when I bought the truck (in winter..but now it's summer)


What it does...


Sometimes it works...sometimes it doesn't. I'll push the button, get ice cold A/C...and sometimes it will just stop blowing cold...I mess with the buttons a few times, it will come back on..then sometimes it won't. I have a 2 week trip coming up and heading to Moab, Utah..and for those who know where that is it's VERY hot in August! I'm not thrilled with going without a working A/C...


Any ideas on where to start? I was told these older trucks used vaccum lines for the switches and I could have a small leak or something? I haven't been behind the dash yet...so who knows. I'm not much for paying someone to work on my truck, so I'd like to get this fixed before the trip.


After this trip...I might be in the market for something newer. Thanks in advance!

 

Bueller? Bueller?

 

if you flip down the glove box you can see just about every vacuum line. does it stop blowing all together or does the air just start getting warmer?

 

first thing check to see if comp is running when it stops blowing cold, second is fan still blowing, if yes to these you have two options, either its a vacuhm hose or the switch assembly itself, but since you play with it and it comes back on id lean to the switch. let us know we can prolly help you out.

 

Thanks guys. It doesn't stop blowing air..so the blower motor is still working. Just gets warm air (not cool at all).


I'll check to see if the compressor stops when it gets warm...I'm hoping it's something simple like the switch or a vaccum line.


Thanks and I'll let you know.

 

These trucks have an evaporater anti iceing sensor at the Tx valve. Look at the suction line next to the fire wall and you will see a small copper tube stuck in a slightly larger tube that is soldered in the suction line. This stops the compressor when it thinks the suction line is too cold. I gently pulled mine out and reinserted it so the end of the sensing bulb is just at the suction line. So far it has worked great with no freeze ups. Also if you run it on Max A/C the water temperature valve is supposed to remain closed. If you run it on regular A/C the valve will open allowing hot water to your heater so you can fine tune the temperature. Check to make sure your mixing damper is closing all the way. It is behind the glove box and is mechanically hooked to the temperature control lever. You can slide the wire in its clamp to adjust.

 

Thanks again, I'll give that a check too.