Heating Problem

[J50]

Heating problem... well, basically no heating at the moment. I'm not too bothered since the car will get little use over the next few months, but can anyone suggest anything to someone like me who is not very technically minded? Basically there is no fan noise when I turn the centre dial next to the handbrake, and there is no heat coming through when driving. I've checked the fuses in the engine compartment and they seem fine.

I've done a search on here on heating problems but for the not-very-technically-minded like me have not spotted an easy solution yet... so any help would be appreciated.

Thanks.

 

[Guest]

This is caused by the corrosion of 2 flaps under the car that direct hot air from the engine into the car.

There is a flap for each side of the car and where they are positioned means that are vunerable to spray from the road.

I'm not too technical and changed mine, see http://www.porscheclubgbforum.com/tm.asp?m=122287&mpage=1&key=heater for costs etc.

Here is a picture of the flaps I took off:

 

[Alan_Armstrong]

I agree with acwats opinion, if you can get underneath, you may only need a good squirt of WD40 to ease things off....it just depends how bad the corrosion is!

I'm not too sure though about the fan not working, unless it is triggered by the heater flaps...also check the fuses in the engine bay, there may be one there for the fans...but dont quote me!

 

[J50]

Thanks chaps. I'll try and check the flaps later, if I can find them! The fuse for the heater in the engine bay is fine; there is a relay there for the heater also, but I have no idea how to check that is functioning, apart from replacing it...

 

[3.2_fordy]

jeremy
When you turn the centre dial do you get a whine from it if you do you can check the heater flaps if you jack the car up and get a friend to operate the dial while you are looking at the flaps you will see if thay are working ie opening and closeing., If thay are corroded open that may be one of your problems give them a good spray with WD or the like and see if you can move them , the cable that operates them may have broken so you could check that
You also have two sensors one controls the compartment temp thats fitted behind a small grille on the dash, you have another sensor on the heat exchanger it may have a short circuit
You have two small blower motors that supplement the main engine mounted fan thay both have a fuse next to them, thay are in the left & right footwells behind the kickpanels
I hope this gives you a few things to check good luck

 

[J50]

Thanks mate.

Now I wish I'd kept the old garage instead of building an extension... it had one of those useful pits in it!

 

[wormand]

I had a similar problem last year. I found out that the relay for the blower motor had packed in. If all the other suggestions fail, I would recommend changing the relay. With the ignition turned on, the engine lid up and the heater control set to hot you should hear the fan in the engine bay. If you can't then the fault is probably the relay (hidden behind the black plastic panel on the LHS of the engine bay), if its not the relay then you could be looking at a new blower motor (£125+). Good luck.

 

[J50]

Ok, thanks! Can I just ask, can the relay be easily tested in some way or is it a case of just buying a new one and seeing if that works?

Also, I think you have to email someone about the membership thing appearing, since the datatbase for this messageboard and the membership one don't synchronise. At the top of one of the forums there is a permanent message about this.

 

[Richard Savage]

ORIGINAL: J50

Ok, thanks! Can I just ask, can the relay be easily tested in some way or is it a case of just buying a new one and seeing if that works?

Jeremy

I had it all! One end - right side - of the control cable to the 'dump valves' had broken. Had that replaced - fun job! - Both of the forward suplementary blowers had blown fuses because they were 'frozen' - freed those and then, having got everything working, the relay went.

I dropped into the local Porsche Specialist and was able to briefly swop the existing relay with one from another cabriolet just to prove it was a relay problem, and it was.

Ordered up a new relay, ouch! and now by 'eck, does it get 'ot in there. Not convinced the temperature sensor is working correctly now!

R.

PS - To see how I feel about Targa's - http://www.porscheclubgbforum.com/tm.asp?m=128170&mpage=1&key=&#129373
- Wana swop?

 

[Guest]

Just to add to my earlier comments:

Prior to replacing the flaps the centre handbrake control switch did nothing, no fans, no whirring nothing......

Once the flaps were replaced all the electronics seemed to kick straight in as they should.

Andrew.

 

[Richard Savage]

Andrew

that's a bit ............... spooky! You must have disturbed something during your pokings and prodings.

R.

 

[wormand]

J50, I borrowed one off a friend. I didn't buy a brand new relay but got in touch with a Porsche salvage place and got one sent straight away. I think is worked out about £30 in the end, but to buy new is £120'ish. All the best.

 

[Richard Savage]

ORIGINAL: wormand

I didn't buy a brand new relay but got in touch with a Porsche salvage place and got one sent straight away.

Anthony

............ an this Porsche Salvidge place is located at ................. ?

R.

 

[Signor]

Greetings
I managed to get my heating system working correctly a few weeks ago, it had a few faults not just one![]
Firstly, the engine mounted blower had worn bearings so the armature seized and popped a fuse, new motor =£149.
Then I checked the flapper boxes, you can disengage the lever from the box between the seats and operate the cable manually, with a squirt or four of WD40, both flaps opened and closed as they should, deep joy.
Now to remove the central control box, I found a couple of micro switches had shifted out of position so the cam assy. wasn't operating them correctly and a found a soldered joint which had broken free so the lead was floating in fresh air! Repaired that lot and refitted the control box.
However the two footwell fans where still not working as they should. With the aid of the good ol' BENTLEY workshop manual I traced the dissappearing voltage problem back to that relay, left of the engine. Took the relay out and opened it up in my workshop and hey presto found a burnt track. After 20 years of passing just too much current the little cooper track had given up! So soldered in a short piece of wire to bridge it and re-assembled the relay.And popped it back into the car.....wait for it.
Bingo[][] now all fans work as they should, more joy (opens can of celebration beer).
Oh and the last thing I had to replace was the fresh air fan under the front scuttle, again worn bearings. It made a hell of a racket when switched on.
The only thing left to do on the heating side of things is too free up the demist lever cable but luckely it's jammed in the "demist" position.
A little summer job methinks.
Any way hope this little tale helps you in your search for heat![8D]