Heater woes with a twist.

Last weekend i was out in the supe and noticed my heaters were not as hot as they normally are. The weekend before they were fine. Now they are warm but cirtianly not 'hot' like they used to be.

My matrix inlet and outlet pipes are the same temperature.........fooking hot! If i turn the air to recirculate then they walm up a little, fresh air and it drops in temperature.

Any ideas guys?

i had the same problem intermitant heating it turned out a heater console change solved the problem

I read your thread buddy. Im guessing yours was the controls either worked or they didnt intermitantly?

Daman your not alone with your problem....if i put it on hot its not hot. But if i turn temperature down i can feel the drop so my controls are working.

As the cars are getting older, the heater matrices are getting blocked.

You could try to flush the matrix through with a hose. Fush it through both directions for about 10 minutes.

You can get some kind of acid used for somthing in industrial heating that Dude used. That worked well, but I've no idea what it is.

As the cars are getting older, the heater matrices are getting blocked.

 

You could try to flush the matrix through with a hose. Fush it through both directions for about 10 minutes.

 

You can get some kind of acid used for somthing in industrial heating that Dude used. That worked well, but I've no idea what it is.

Thanks for the reply guys

Matt, when you say flush it im guessing stick a hose on either end of the inlet and outlet pipes located at the back of the engine bay behind the rocker cover?

Thanks for the reply guys

 

Matt, when you say flush it im guessing stick a hose on either end of the inlet and outlet pipes located at the back of the engine bay behind the rocker cover?

Yep. One from a hose outlet, the other hose down drain. Then reverse after about 5 minutes, re-flush for another 5 minutes, then re-connect the engine hoses.

I read your thread buddy. Im guessing yours was the controls either worked or they didnt intermitantly?

correct. on or off or luke warm lol

Yep. One from a hose outlet, the other hose down drain. Then reverse after about 5 minutes, re-flush for another 5 minutes, then re-connect the engine hoses.

Ta very much, guess what ill be doing at the weekend?

What are my chances do you think, and after that is it thermostat time?

Ta very much, guess what ill be doing at the weekend?

 

What are my chances do you think, and after that is it thermostat time?

Thermostat? - I doubt it to be honest, after that, it's heater matrix time!

Thermostat? - I doubt it to be honest, after that, it's heater matrix time!

Im in denial, and ignoring that you ever mentioned that

changeee the switcchhhhhhh

update

As the waether was on the poor side and im a fairy i didnt flush the matrix, i now dont think this is the problem.

When turning the temperaturte dial every notch turn is followed by an electronic movement of some sort (im guessing its this imfamous flap?) however after 27 there are no noises nor are there any changes in temperature, so it looks like i get 18 - 26/27 and no futher..........ideas anyone?

Another Update

Heather control pushed in a bit = fooking hot air!!!!!

Still intermitant, maybe now ill try a new switch!

As the cars are getting older, the heater matrices are getting blocked.

 

You could try to flush the matrix through with a hose. Fush it through both directions for about 10 minutes.

 

You can get some kind of acid used for somthing in industrial heating that Dude used. That worked well, but I've no idea what it is.

Nitrox

Hi My Mk 4 is feezing cold! So driving my Mk 3, 2.5TT.. Flushed the matrix with two bags of descaler crystals. after leaving over night. Twice. Also replaced the front panel control unit... All I hear is the panel to make it go from internal to external air. So where is "that flap" how is it controlled.

I assume its also a take radio out... So cold cant even work on her for long...

Ok, heater control unit swapped for another one.

18 (or what ever it is) to 26 = fine

26 to 32 = computer says no!

However its intermitant

Turn the dial up and down a handful of times and then i get hot air.

Weird Daman. Problem with the connection, loose wiring on replacement unit maybe or did it do this before too?

Have you flushed the Matrix yet as per Matt Harwoods advice?

Greg

Drive for 20 minuites so that it warms up, stick the fan on and turn the temp upto full. Its cold, not compleately cold but almost too cold for this weather, i recon the true output was around 23/24. However i hit the "aim at feet and face" from "aim at face" button and instatly hotter air, almost what 32 should be. (it may have even been 32 but i cannot remeber what that feels like now )

I had a little fiddle, engine running, fan at 1 and stereo off. If i turn the dial notch at a time from 18 upwards each notch produces a sound from behind the dash (this maybe this mistery flap) after 26 the sound is non existant. 26 downwards also causes the notch noise except the turn from 26 to 25 (the first one) produces a much louder and longer notch noise/flap

Could some of you guys with working heat describe your 'notch noises'?

Greg, im convinced it doesnt need flushing. 2 Units, 1 problem, i dont think its the control unit. Bloody thing

any luck with this daman, mine is in a worse condition than urs, i only get the 'big' noise (flap thingy) when going from 20 odd degrees up. and get no more sounds after that at all. i have flushed the engine before and that semi cured the problem to roughly what you were suggesting, working upto 27 odd but not after. going to search out this nitrox stuff and try again.

if you should bite the bullet and buy a new unit from toyota a part number would be greatly appreciated.

thanks and good luck

Rob

You could always go for TrickTT (Rich's) offer of a practically new Heater Matrix fully fitted for under £600 of course! Far cheaper than anyone else out there!