How long should Fan run for after car is switched off.

[smagerstein]

Hello All.

As I am new to Boxster ownership...2 weeks now!

I have a simple question.

When I drive my car daily to work....... (About 15 minutes of highway driving. Usually sit on about 80 - 90 mph. Always warm up for 5 min before leaving in morning.)

When I stop, the exhaust fan on the vent on passenger side will run for at least 10 minutes to 15 minutes off and on after I have turned my car off and locked it.

The car has a 12 month warranty so if anything is wrong then all will be covered by the only Porsche dealer here in Slovenia.

Just wondering if this is normal.

Thanks.

Steven.

There is no need to pre-warm your car for 5 minutes in the morning before you leave. This just wastes gas and can actually harm the car. You can idle for about 10-60 seconds, and then drive. Once the car has come-up to normal op temp (engine temp and tranny loosens up- oil temps quickly mirror engine temps) you can increase RPMs over the 3,000-4,000 range. This would be much improved to sitting for 5 minutes.

As for your fans running after the car shuts off...I don't know what is considered normal, but I am sure you will get your answer here soon.

[smagerstein]

Thanks for the feedback mate

Steve, when you say the fan runs "on and off"...do you mean sometimes it does it and then another time it does not? Or do you mean that the fan actually turns on, turns off, and then again on & off?

[smagerstein]

I mean it turns on...goes for a couple minutes....turns off for a minute....turns on again.....etc.

maybe stops and starts 3 or 4 time before turning off completely.

It does it perhaps 2 out of 3 times i drive the car for more than 15 minutes.

OK, this does not appear normal to me. My guess is some type of temp sensing device is not working properly.

Someone here will give you better advice about in than I can. Sorry.

[smagerstein]

mmmmmmmmmmmmmmmmmmmmm

Think I will get it checked out Monday!

Cheers

[Adam]

Originally Posted by smagerstein

I mean it turns on...goes for a couple minutes....turns off for a minute....turns on again.....etc.

maybe stops and starts 3 or 4 time before turning off completely.

It does it perhaps 2 out of 3 times i drive the car for more than 15 minutes.

That is odd and I've never heard of it switching on/off multiple times after it is shutdown. I would maybe wait and see if anybody else can chime in here but that should probably be looked at.

[MNBoxster]

Hi,

The Engine Compartment Purge Fan (Porsche Parlance) certainly can come ON/OFF multiple times, but should it? The Fan is supposed to turn OFF once the Engine Compartment temperature drops below a given threshold - 185°F (85°C).

Unless there is a Heat source adding additional heat, the Fan should remain OFF once the temp drops below the threshold.

What I suspect is that your Fan is turning OFF prematurely before dropping below this temp threshold. I suspect the reason for this is a bad Relay.

The failing Relay heats up when energized and causes the armature to disengage, breaking the circuit and shutting off the Fan. Once the Relay cools sufficiently, the armature re-engages, closes the circuit and starts the Fan back up because the Engine Compartment temp remains above the nominal temp threshold. This cycle continues until the required Engine Compartment temp is achieved, explaining the multiple ON/OFF cycles.

Replacing the Relay is a simple DIY project - pull out the old one and insert the new one. Cost is $7-$24 USD for the part depending upon whether you source the part from Porsche or not. It is Relay #8 (2nd from the Left on the Bottom Row) in the rear Relay Block. Hope this helps...

Happy Motoring!... Jim'99

[smagerstein]

GREAT!!

Will pick part up in the morning and try.

Thanks

Steven.