Hey guys,

Since the temperatures here have dropped below 0, my heat has been sporadically working. The blower and heating unit sometimes work immediately, at times it works after 10-15 mins, and sometimes it doesn't work at all. I just drove home in -6C temperatures with no heat (30 min drive).

I had no issues at all throughout the summer with my AC. The issue just started happening recently as the temperature have been dropping significantly.

Is there a known issue or part I should look at?

Thanks all

 

Man hope you find your issue. I myself have no heat as my core is bypassed via pre owner

 

Yup, it's brutal!

 

OP, it could be a lot of things. Does your temp gauge go to the normal operating temp? If not, check coolant level. If it is full, it could be an issue with your thermostat being stuck open and not allowing your engine to heat up properly.

Are you using climate control or have it set on manual and adjust the fan speed settings? If you are on climate control and your engine temp isn't warm enough your motor will take a long time before your heat will run if it starts at all.

If your temp is normal it could be our blower motor or loose wiring.

 

Why on earth did he do that? Was it leaking or otherwise plugged up?

I wouldn't buy a car where an owner did that. It generally shows that the previous owner either didn't take the right steps to fix a serious problem with the heater core (and who knows what else he may have half a$$ed), or he was doing something race related with it where maybe he wanted less strain on the waterpump to maximize every little bit of engine responsiveness and power. Turning the heat to the off position should basically accomplish the same thing as the disconnecting it though as far as the second option is concerned since it basically bypasses the heater core by doing this, but leaving it connected could actually help the car cool a bit on a hard track session by turning the heat on and blowing it into the car so that the heater core will shed heat like a small radiator in the event of the stock radiator being unable to keep up with heat production.

 

Coolant levels are good, car doesn't overhaeat and it runs at normal operating etmp.

I usually have it set to manual but I tried the climate control feature, nether work. The thermostat crossed my mind but if that was the issue, would the car not operate at normal temp levels and potentially overheat?

The blower motor is starting to sound more likely. Should I just swap it out or is there a way to test it to ensure 100% that the part is faulty?

Thanks for the response!

 

Could be the blower motor or even the controls. I would check the wiring first. If that doesn't solve it, I would have a shop look at it before swapping parts out.

 

One cool thing about modern cars is that there is a self-diagnostic procedure you can do to verify what's not working. Photobucket seems to be blocked at work so I can't post screen shots for you, but look at the ATC section of an FSM (factory service manual) for the troubleshooting steps of "insufficient heating."

The first step is to verify the symptom: warm car up, turn temp dial to 90 degrees and check for warm air coming from the vents.

From there the self-diag feature will check the controls, then check sensor circuits, then LAN and blower motor circuits, then it has you check coolant levels, hoses, and for air in the system, then check the heater core itself.

EDIT:
Added screen grab of the inspection flow for no heat. You'll need to view the FSM for putting the system into self diag mode, it's several pages.