Bobgenie's roadgoing 2+2 300ZX (ex Madmax) only blows hot air (a bit like its owner:lol:)

Its a series one set up.

Any thoughts on what is wrong?????????????????

Watching closely as mine does exactly this. Apart from one morning it decided to blow cold instead. Pretty sure a motorised valve has jammed in the hot position.

Watching closely as mine does exactly this. Apart from one morning it decided to blow cold instead. Pretty sure a motorised valve has jammed in the hot position.

Cheers for that.

That would expain it possibly

 

Anyone alse got anything to add

Or disagree etc etc

 

Or any offer to fix it for Bob??? (Payment if required)

From what I've understood there is a motorised valve that opens the flow to and from the block allowing an amount of hot engine water through the heater matrix, bit like a heater in your house. I also think its down behind the stereo on the drivers side. I've so far decided to just open the window and forget about it haha.

I think a conzult runs a check on these valves etc, have you hooked it up?

I think a conzult runs a check on these valves etc, have you hooked it up?

 

No mate. I dont have the car .... or conzult.

Bob has the car but it runs an AEM ECU.

Pretty sure the water valve is cable operated,could be wrong tho'-been a while!

I would certain be checking the valve for correct opening/closing tho mate..............

The auto aircon uses 3 motors to adjust hot / cold, recycle, and direction. Theyre in behind the centre vents i think

Pretty sure the water valve is cable operated,could be wrong tho'-been a while!

I would certain be checking the valve for correct opening/closing tho mate..............

 

If I had the car here YOU WOULD be checking it all for me!

 

Or any offer to fix it for Bob??? (Payment if required)

There is also a self diagnostic to check the actuators, accesed by holding auto and off buttons for 5 seconds. Details in ha section of the service manual. Not sure how to post the relevant pages

There is also a self diagnostic to check the actuators, accesed by holding auto and off buttons for 5 seconds. Details in ha section of the service manual. Not sure how to post the relevant pages

 

Thank you.

 

Hopefully Bob is looking in to this and making some notes!!

Ha page 98

 

2 motors attached to the bottom of the heater unit. The motors rotate moving a lever system which varies the air mix door to heat or cool the air.

A sensor in the duct sends information to the auto amplifier which decides how to adjust the door

 

Looks like one motor moves it to hot and the other to cold?

 

Or the sensor is broken so the auto amp doent know the air is hot, so keeps trying to warm it to the selected temp

Actually looks like both motors move together, so i would go with door broken off lever or more likely sensor problem

There is an air sampler in the little console were the map lights are, I removed mine because the little fan was noisy, now its confused and only blows hot air...(again, like the owner)

I changed the control unit but still the same only hot air. Here is a pic of what shows the -86 is always there so any knowledgeable people know what this means?

 

I've got a spare ECU but wanted to wait see if the pic means anything before I take the plunge.

Founds like the sensor is faulty then and trying to heat you up to temp.

That's the ambient temperature which the sensor is connected to the front bumper.

Don't know how to link, so......

If you look a few posts down below yours in the help and advice section. I have a thread entitled "windscreen demister".

In there is a link to the service manual diagnostic procedure (pdf file).

Hope that helps ;)

Page 85 I think mate.

Also see page 82. (symtom chart)

 

http://stadzport.com/FSM/HA_Heater_Air_Conditioner.pdf

Edited August 26, 201312 yr by redwine300

Thanks guys will have another look today :)

Here's a pic of amb temp sensor. But my guess is one of the temp sensors in air ducts is gone. I had the same problem