2nd gen dash controls

Hey guys. Remote started my truck the other day (and ever since) and went out to find it was blowing cool air. Once I took off, it went hot. So I am suspecting a vacuum leak. I figured all dash controls would be electronically controlled on these trucks, but I have heard my truck over the last few months randomly making some groaning and farting sounds after shutdown, so that all leads me to believe vacuum leak or a bad diaphragm. Those sounds were coming from center of dash/firewall area. Is anyone aware of any common problem areas or components there? Not really trying to rip the dash apart if I dont have to. Thanks.

 

Have you checked your coolant level? Classic symptoms of low coolant right there.

 

To be honest, I hadn't because of the under dash groaning. I felt like that was a certain vacuum problem. However, I now checked it and I am low. I will fill and retest.

 

The groaning noise you're hearing is likely the AIP system purging itself and also possibly the blend actuator door closing. Both perfectly normal. I don't have a remote start on my '13 but it does take a few minutes to warm up to the point where I can feel warm air.

 

Air pockets flowing through the heater core will make neat noises too. Burbling and groaning.

But yes, one or more of my air doors can be heard a couple minutes after key-off too. It groans.

There is no vacuum lines inside the dash of a Tundra. All electric actuators on 2nd / 3rd gens, and a mix of cable control / actuators on 1st gens depending on years.

 

OK, thats kinda what I was thinking. So it is almost certainly just low on coolant. Just got a couple gallons. Ill mix them up and pur them in on my lunch, and all should be well when I fire it up to leave tonight.