Hello all, I wasn't too sure where to put this post,so sorry if it dosen't belong here but here is my problem.....I have a 2001 2500hd with 178,000 miles,recently the a/c began acting up,it will just stop working,not just stop cooling,but stop blowing...nothing happening. It is an intermitent issue and has no real method to its madness. It works fine then next thing you know nothing,then it will start working fine again.

I got the same problem with mine.
Maybe someone who has had this problem before will chime in.

Mine still blows air, but it's hot. Found this searching the forum yesterday:

http://www.dieselplace.com/forum/showthread.php?t=253730

do the bypass on the Heater core and enjoy ARTIC AIR!!!!

If the blower stops blowing air, then most likely the "blower resistor" and/or it's connector are going south. There are hundreds of threads on here about "blower resistor" failures. Unplug it, inspect the plug for loss of tension in the terminals and melting, then pull out the resistor and do the same.

mine has eaten 4 since i owned them, all go out right after the 1 year mark=
NO WARRENTY:mad: there like 69 bucks

mine has eaten 4 since i owned them, all go out right after the 1 year mark=
NO WARRANTY:mad: there like 69 bucks
Sounds like time to change the 7wire connector:rolleyes:.

As far as the A/C blowing hot air intermittently, which is what happened to mine, turned out to be the pressure switch. I can't remember if it was the high or low one, but it would work really well around town but then out on the highway over a period of time hot air would come out. IF you turned it off for an hour or two it would start working for a little bit, not as long as the first time, then hot air. Changed the switch and no problmes yet. The blower issue I agree with the above. The resistor pack can build resistence (intermittent problem) and then when it gets hot enough burns out completely.

Jp

I agree with the Blower Resistor mine did the same thing about working and not working. Changed the resistor and it works great, it also helped with some of the noise that I thought was the fan.

if your getting "hot" air with the a/c on, the motor that closes the "flap" between the two compartments is out!!! my brothers went in winter that wouldnt switch to heat, so he was stuck without any till it was replaced.

oh yea, And once your problem is fixed, I STONGLY Suggest EVERYONE add one of these to you truck!!!!! I am talking probably another 10 degrees colder then what yours blows now, and it doesent fluctulate?? it is cold and stays ARTIC COLD!!!!

is that just a valve in the heater line? anything special or hard ware store parts?

its hardware store time....
97-100 degrees here....I could use a couple of degrees on the a/c

i Cannot Urge Everyone Enought to do this, The air is so UNBEIVABLY COLD!!!!! , I choose the brass valve and fittings becouse the Schedual 40 plastic has a melting point of 220 degrees f. and that is jsut to close to call. the hole thing cost me 18 bucks, well worth it. Hardware hank was the store, but every hardware store should carry the fittings.

Be Aware!!! there is some discussion on the fourm about blocking the EGR when the mod is done. If you have a LLY, LBZ, LLM, research at your own risk. i have a LB7 with no EGR.

Thanks to DIESELPLACE.com i now can make the girlfriend's Nipps come out of hidding, HAHA

Where is the blower resistor located at, and how much should it cost.

Where is the blower resistor located at, and how much should it cost.
Follow the link here in post #3 http://www.dieselplace.com/forum/showthread.php?t=231606&highlight=blower+resistor

I love the search feature:D.

isnt the heater core a bypass when the thermostat is closed??? or is that just other engines?

isnt the heater core a bypass when the thermostat is closed??? or is that just other engines?

IIRC, on these trucks, the core recieves full circulation and heat from the coolant. The air flow is directed around the core when cold is selected and, therefore, the HVAC unit always has a hot core, which warms the whole shebang, and, of course, leakage of air around the selector door.

IIRC, on these trucks, the core recieves full circulation and heat from the coolant. The air flow is directed around the core when cold is selected and, therefore, the HVAC unit always has a hot core, which warms the whole shebang, and, of course, leakage of air around the selector door.

what im asking is can you safely bypass the heater core without interupting the coolant flow when the t stat is closed

ok tried the valve....at first i thought it didnt do anything but after running the truck for a good 15 its damn cold coming out the vents.....

still not sure if im hurting anything by blocking this off......03 duramax

EDIT: oh by the way you can use a 3/4" pex valve and thats all you need no extra fittings....$8

ok tried the valve....at first i thought it didnt do anything but after running the truck for a good 15 its damn cold coming out the vents.....

still not sure if im hurting anything by blocking this off......03 duramax

EDIT: oh by the way you can use a 3/4" pex valve and thats all you need no extra fittings....$8


I TOLD YOU!!! Mine is a 03, just do some research on here, it is ok your not hurting anything.