I have had 2 different mechanics look at the heater in my truck, the thermostat replaced several times, and the heater core replaced. the last guy to check it out said thats as good as it will get. this just seems crazy to me. it has to get better than that. also, since ive had the truck my interior lights wont work, the dome light and map lights. the temp display did work and just went out one day. any thoughts are helpful.

 

i would check all the fuses and grounds. theres one under the hood to called ign off draw or something along those lines that might be blown. my friend has this same electrical problem on his jeep and we tracked it down to a short thats blowing the fuse.

 

no heat as in no air blowing or no heat as in air not heating up?

my 92 has little heat takes forever.. i removed the fan totally(mechanical clutch was locked on) and temp gauge still barelly moves (only about 1/8 and never to operating temp) but it does keep truck decent enough

 

Thanks for the info on the fuse, sure enough it was blown. Now with the heat it does get warm but not enough to keep the cab warm. it blows fine, i did have some issues with that but got it fixed. i just cant believe it wont get any better than that.

 

well it will heat my cab just takes a real long time ....

being age have you tried backflushing the heatercore with a garden hose attached ?

 

I had it flushed a few years ago but that was before i had the heater core changed. i will give it a try. i usually don't drive it in the winter because it wont get warm enough. i live in Indiana and we have some really cold winters

 

Heat, here in Sunny Tucson, isn't the highest priority so most of this is from memory.

Been kinda lurking the "no heat" threads. I think I'd back flush or even de-crust the heater core. If you've used anything other than fresh coolant and distilled water you may have some calcium or rust deposits in the core (rust deposits from the engine block/heads/etc.)

You can 'de crust' the core, and your radiator, too, with CLR--which will dissolve rust and calcium. To do the whole system, drain it, pour in a bottle of CLR, and fill it up again--run the engine 'til op-temp is reached and then a little more, let it sit a while (oh, like 1/2 to 1 hour.) Flush the system--heat cycle it, and then flush it again. You don't need to get all of the CLR out, just a big majority.

While you have things drained, you might install a 185 degree thermostat, too.

To do just the core, pull both hoses off the engine, drain, flush, the add a 50% mixture of CLR. Hang both hose up so the mixture doesn't drain out, let it sit for the aforementioned 1/2 to 1 hour, then drain and flush with lots of water.

Sorry, guy. I know it's cold out to be working on your truck. I guess you could pay someone to do the work.

NEVER use tap water in the coolant system (or the battery.) None of the minerals in tap water are good for your truck.

If you still don't have heat, you got other problems like leaky seals in the HVAC box. It means that you've got to take the dash apart and fix those seals.