I'm worried my heater core and vacuum pump are failing. Two weeks ago people started asking me what the "anti-freeze smell" was when near my truck while it was running. Last week if my heat was on I could smell anti-freeze through the vents, and even it if it was off I could smell it if I ran the truck hard through town. I already tested the coolant system pumped up to 17psi repeatedly, and repeatedly lost pressure....sometimes very quickly down to 13-14psi. I have no visable leaks underneath the truck, but have had to add nearly 1-gallon of coolant. The inside passenger floor is not damp, even under the carpet.

Yesterday morning I went from having full use of any/all vents & defrost to defrost only. Normally this is just the little hard plastic line at the vacuum pump popped out of the rubber boot. This time its still zip tied in place? :dunno Also I have no 4 wheel drive. Went and had it looked at last Monday (30th) tech supposedly found cracked plastic boot @ the cad and put zip ties on the boots to hold vacuum. Worked when I got the truck back on Monday, but when I tried to use 4wd Friday night didn't work. Still doesn't work even though I added new vacuum line from the metal lines on the frame rail down to the CAD. Is there a way to test the vacuum pump?

TIA
Mark

 

oil in your vaccum lines will make anything that works off vaccum quit. If you have oil in your lines you need to replace all of them and check to see if your vaccum pump has the check valve on it there is a tsb on this. The new check valve is supposed to stop oil from entering the vaccum system. If you had oil in the lines the cad is probaly gumed up try cleaning this out.

 

sounds like a bad heater core to me with the smell. usually youll get symptoms like damp carpet, antifreeze smell, and a fog on the window with the defroster on.
Its a royal pain to get to Id imagine. you might want to pay someone to replace it.

 

A quick way to test the pump is to unplug the fitting off the pump and check for vac there. I've seen the 90 degree fitting at the pump get mushy from oil and collapse. There should be at least 8.5 in vac . There is also a low vac warning switch that should light up in the dash if the vac drops off.

 

Wash the inside of the windshield, then run the truck with the defroster on. Any slimy film would lead me to a leaking heater core. While your at it, check you oil and tranny fluid for antifreeze.