Heater problems; Solved

[swiftie]

Recently had dealer installed new turbo (4.5 lt V8 Diesel UK spec) and this was an engine out job. On returning the car the heater is intermittent. Blows cold on auto while engine heats up then is okay while moving (auto reduces fan speed and temp) On stopping blows cold air again until you get to speed then fine ? Very odd Any ideas ?

 

[bloc]

Recently had dealer installed new turbo (4.5 lt V8 Diesel UK spec) and this was an engine out job. On returning the car the heater is intermittent. Blows cold on auto while engine heats up then is okay while moving (auto reduces fan speed and temp) On stopping blows cold air again until you get to speed then fine ? Very odd Any ideas ?

Probably air bubbles in the heater cores. Usually some spirited driving will flush them out.. not necessarily high power or hard acceleration, just more RPMs than the minimum needed to drive around.
Try using your S transmission mode to hold the RPMs up for a minute or two and see if the situation gets any better. I’m not sure whether you have rear AC but when I drained and flushed my cooling system I got some air back there and it would not blow warm at all until I did that.

 

[swiftie]

thanks will give it a go but it seems more sensor related ? Maybe ambient sensor off. What seems odd is how I can get heat so long as I'm moving but not stationary when it then starts blowing cold again. Odd I must admit to being a bit lost as to the reason

 

[bloc]

thanks will give it a go but it seems more sensor related ? Maybe ambient sensor off. What seems odd is how I can get heat so long as I'm moving but not stationary when it then starts blowing cold again. Odd I must admit to being a bit lost as to the reason

Now that I think about it blowing warm then cold again undercuts my air bubble theory. I’d think once they were flushed out they should stay out. Still, might be worth a shot.
If you can get access to a working techstream system you should be able to get a live readout of what the sensors are showing. Plus you can do a “servo motor initialization” which toyota says needs to be done any time the battery is disconnected.

 

[swiftie]

Well it can go back to the dealer I think and they can sort it. I don't have Techstream (although I'm thinking it might not be a bad idea to get it) Thanks for the reply. Never know someone might have had a similar issue and see this thread.

 

[swiftie]

Now that I think about it blowing warm then cold again undercuts my air bubble theory. I’d think once they were flushed out they should stay out. Still, might be worth a shot.
If you can get access to a working techstream system you should be able to get a live readout of what the sensors are showing. Plus you can do a “servo motor initialization” which toyota says needs to be done any time the battery is disconnected.

Actually you were right. Checked header tank and it was empty. Refilled once plus as top up and heater is now 100%. Obviously heater circuit air locked when the turbo got fitted. Turns out it was rpm not speed which was the issue. Thanks. Hopefully someone will find this one day and yet another solution sorted on here !

 

[bloc]

Actually you were right. Checked header tank and it was empty. Refilled once plus as top up and heater is now 100%. Obviously heater circuit air locked when the turbo got fitted. Turns out it was rpm not speed which was the issue. Thanks. Hopefully someone will find this one day and yet another solution sorted on here !

Glad you got it figured out, and thanks for the update