My fuel pump went out a couple of years ago. It ended up sitting as a buddy was going to help put it in but that never happened. Finally towed it to my local shop and they installed it. Did a check and did an olf. Nice to have it back on the road. May need a battery, not sure yet. Picked it up and drove home. The temp guage never got above 110. Heater was warmish but never really got as warm as it should of. Drove about 25 miles so the Tstat should of opened? Wondering it is is stuck or bad. Going to get very cold out. Any problems possible due to the extreme cold?

Replace the Tstat gasket and antifreeze. It should then be ok unless you are low on antifreeze and no coolant is getting to the heater core.

Sounds like the T-stat is stuck open. Replace the T-stat and you should be good.

Thanks guys.

Like greco said, check the coolant level first. If it's low,fill it first but pull the engine oil dipstick to check and see if for any reason coolant had leaked into the engine. Anti-freeze will destroy engine bearings pretty quick. Most likely a bad t/stat but you have to make sure.

One other thing to consider is that the antifreeze blend may cause your temperature gauge to read incorrectly if too much water was used or topping off frequently. Some GM vehicles factored in the electrostatic variables of the coolant to read temperature and adjust the injector pulse width to maintain an optimal air/fuel ratio. Another factor would be if the heater inlet valve isn't opening properly. Many are vacuum activated. Later a bimetallic spring was utilized depending on the year of manufacture.

To check for a open thermostat, take off the radiator cap and start the engine. If you see the coolant being circulated when the engine is first started, the thermostat is likely stuck open.

A simple scan tool (if available) will give you the measured temperatures of the air, coolant, etc. Running the engine in this way will also lead to a saturated catalyst and premature cylinder wear.

So it was low on antifreeze. They said they checked it. Don't think they did.

Seem's to come up past the 110 on the gauge now. I am going to take on a longer drive soon.

Another question is that the fan does blow with the force and volume it should. I think the fan is running fine and all the different speeds. Just not blowing through the vents like it should. The defrost seems better than when on the heater settings.
The van sat for a couple of years. Wondering if I got mice nest's in ducting. How much of a B---ch is it going to be to figure that out in an older Astro van? Any idea's?

I think your ducts are plastic and just under the dash. I dont know if pulling any panels is required. They should have dampers inside which change the air flow direction. If you can disconnect the duct carefully you can inspect visually for blockage. Could just be a spring loaded damper not moving freely.

For the dash vent issue, check the vacuum lines under the hood from the engine to the doors. They run partially around/under the A/C accumulator. Replace anything rotten or broken.

quote:

Originally posted by egregore:
For the dash vent issue, check the vacuum lines under the hood from the engine to the doors. They run partially around/under the A/C accumulator. Replace anything rotten or broken.

Is there a valve on the heater hose that is vacuum operated? If so a vacuum leak may be causing all his grief.

I don't recall any heater control valve on Astros. The dash vents themselves have vacuum-operated doors. If the vacuum source is lost the default position is defrost.

If this is an older one with vertically sliding levers for vent and temperature control, sometimes the control itself goes bad, in some cases actually making a hissing sound. This does not apply to the rotary knob control.

Plenty of vacuum control on an Astro, including the heater control valve.

Visit www.astrosafari.com for lots of info, pictures, diagrams, help...

Blower motors, resistors and wiring can be rather problematic. The blower motors are brush motors and sometimes they can be cleaned out to live a little longer. The wiring to the resistor apparently isn't quite the right size and the high speed pin will burn up pretty good, then the other speeds will surely follow. The resistor's original design wasn't so great and could take out both the wiring and the blower motor; the replacement design is a pretty good upgrade. All of this is on the passenger side, including the vacuum lines, check valve, line to the heater control valve and vacuum reservoir, line that crosses over the motor to the driver's side head.

All of that is easy to get to. Pull up the radiator overflow and washer reservoir, disconnect the pump harness and twist it out of the way, keeping the washer and radiator hoses attached.

Inside, you've got a vacuum pot just behind the bottom right of the passenger side knee bolster. All other vacuum lines are behind the doghouse and the heater controls. The blend door actuator is under the doghouse, against the driver's side of the blower motor housing (black actuator on black plastic, so use a light). There are 5 plastic gears inside that can crack and jam.

If you pull the blower motor out, there could be a rat's nest of crap in the housing. There is a filter on the other side of the evaporator housing from the blower motor, but I've never had to clean or replace it.







Oh, and the blend door actuator guts: