MA61 + 1JZ + Heater problems

[Gibbon]

Hi

Got a 1JZ in my MA61 - it's getting a little cold in the mornings in the sunny ACT now, so it's time to start the heater up - except, nothing comes out except cold air

The heater used to work before the conversion - I had the temperature sensor in the center console disconnected for a while, and it only blew hot air.

I have checked the VSV - and according to the TRSM troubleshooting steps it seems to be working fine. I'm a bit confused about how the plumbing works.

In this pic the hose comes straight off the engine and into the heater core (top connector in the firewall)



In this pic, the yellow hose goes to the other heater core connector in the firewall, and the blue hose goes to the engine.



All three of the hoses are cold while the engine is hot. I would have thought that at least one of them (maybe the blue one) would have been hot, but the hot water wouldn't have got through the heater tap until needed - but they are all cold.

Squeezing the hoses while the engine is off I can hear water sloshing around inside them, and also hear it sloshing around the radiator hose - so it doesn't seem to be a blockage.

Any ideas on what to try next?

Thanks

[Dale]

So the heater has never worked since the conversion?

I tend to think that the hoses might be on the wrong way around.. does it have climate control or analogue? Might be a wiring issue of some kind if its climate control

[Gibbon]

So the heater has never worked since the conversion?

I'm fairly sure it did - but I did the conversion at the start of summer - so haven't really thought about the heater for awhile.

I tend to think that the hoses might be on the wrong way around.. does it have climate control or analogue? Might be a wiring issue of some kind if its climate control

Climate control - but doesn't heat up using that or just the fan on manual. Sideshow did the wiring, so it's been done properly.

I'm also wondering about the hoses - they just don't seem to make sense to me - but I would like to see other 1j's in a Ma61 before I swap them around.

[ViPeR_NiPPleX]

the hoses are right from the heater tap, it's possible it had seized. Also possible the heater core is clogged? Double check the vacuum source for the tap too...

[Gibbon]

the hoses are right from the heater tap, it's possible it had seized. Also possible the heater core is clogged? Double check the vacuum source for the tap too...

The core was supposed to have been replaced in August 2005 (according to the receipts I got with the car).

Vacuum source seems ok - from the heater tap it goes to the VSV, and from that to the engine.

So it might be the heater tap then?? Anyway to test it?

[ViPeR_NiPPleX]

take it off, blow thru it? run some clear vinyl hose from the outlet to the heatercore?

[Negative Boost]

I've just recently found out my heater dosn't work either now after my 7M conversion. I'm sure it worked for a couple months afterwards but i get the same thing as you now, warm-cold air.
I replaced my heater tap with a spare last night and inspected the one i put in by pressing on the valve which moved freely. I also inspected the one i pulled out and that valve moved freely too. Needlessly to say, i still get warm-cold air. I'm now planning on bypassing the heater tap all together to rule out a blocked core. Thats the last thing i want to replace!

[Gibbon]

Ok -bypassed the heater tap - still get cold air

Does that mean it's a blocked core ? - Please say it isn't so

Both hoses going in and out of the core through the firewall are hot, as are the metal connectors poking through the firewall.

[thechuckster]

you should check that:

-the vacuum operated air control lever (visible behind the radio) operates when you turn on the fan anc change the temp settings (with the engine running). t hat lever controls the mix of hot & cold air

-the two temp sensors attached to the tap are connected and are seeing hot water (one is so the heater doesn't try to work if the coolant is cold, the other is to see if coolant is over 50 degrees)

-did the vacuum operated water switch operate when you shift the temp control from cold ot hot (with engine running) - if not then you need to check if the VSV valve is working.

The TSRM also has a few diagnosis suggestions.

From here onwards helps you troubleshoot this part of the climate control.

The usual cause of hte heater not working is one of the sensors not plugged in or the vacuum supply to the water switch setup not right (e.g. seeing boost).

cheers,
Charles.

[BlackSupra]

chuck is correct.

Had the same problems with mine when the heater didnt work.

Check that the VSV line to the tap gets vacumn.

If the two plugs are around the wrong way under the tap, it wont work.

As chuck mentioned look behind the radio, when the heater comes on everything is vacumn operated and a slide is actuated, you should see the slide in action when the tap is opened, if not, check the vacumn line. My exact problem was that the actuating arm for the slide had jammed back on the vacumn line, kinking it, preventing any vacumn from getting through, and thus not allowing the actuator to slide.

Also make sure the solar sensors in the dash and both ambient sensors, one under center console and one at front of car are connected.

+ rep to chuck.

[Gibbon]

Thanks - I'll try those.

But at the moment, I have bypassed the water tap completely, and it's still just blowing cold air.

Is there something else that controls the flow of hot or cold air through the heater core?

I would have thought that by running hot water into the heater core, it would have no choice but to blow hot air into the car.

[BlackSupra]

Thanks - I'll try those.

But at the moment, I have bypassed the water tap completely, and it's still just blowing cold air.

Is there something else that controls the flow of hot or cold air through the heater core?

I would have thought that by running hot water into the heater core, it would have no choice but to blow hot air into the car.

only if the mixing slide behind the radio changes to hot air settings and changes the mix to hot air.

[Gibbon]

only if the mixing slide behind the radio changes to hot air settings and changes the mix to hot air.

Ok - out comes the radio then.

I think I can rule out a blocked core.

I disconnected the top hose (near the turbos) that goes straight into the top heater core connector in the firewall, and blew into the hose.

Water immediately came pissing out of the ( now disconnected ) metal connector on the engine - which would indicate to me that there is a clear passage all the way through the core and around the engine and hoses back to the disconnected hose.

Thanks

[thechuckster]

is likely that the wiring or plumbing for the climate got screwed up during the conversion.

When i got my car. i discovered that there was no vacuum source for actuators inside the cabin (pipe had been conventiently blocked off).

[Gibbon]

is likely that the wiring or plumbing for the climate got screwed up during the conversion.

Even if the wiring for the climate is screwed up - having no water tap (just the hot water straight to the heater core) and the fan on, why wouldn't I get hot air ?

I'm trying to take the electrics out of the equation to narrow down what could be at fault.

My limited understanding of how the heating works is:

- Air is drawn into the car (either internally or externally via vent)
- If heat is selected on the manual slider, it directs the air over ( through ? ) the heater core, and then to the vents.

Would that be right, if it is, then there is no vacuum or climate controls issues to worry about?

Cheers