Vents & fanspeeds...

[mbrands]

Firstly, did Porsche ever offer an uprated fanspeed for ventilation system ? The reason I ask is that 5 years ago I used to own an R-reg 993 C4 Cab and the fan speed was pretty decent. On a cold sunny day you could drive with hood down windows up and heaters on full blast and be comfortable. At full blast the fan speed never felt like you needed another notch to turn it up even higher. In other words, there was a good blast of air coming from the vents.

Fast forward 5 years and I now have an R-reg 993 C2 coupe. The fan speed feels nothing like what I remember on my old C4 Cab. Full blast feels like it's on medium strength (if it were a cab, you would freeze on a cold sunny day with the roof down) , yet a check on the diagnostics machine says that every thing is OK and reports no faults with the system. And if you ask a technician, they shrug their shoulders and say the ventilation system has always been poor.

Seperately, and possibly related to this is the fact that my left centre vent does not get much air coming out of it. With both centre vents open, you'd think the airflow out of left and right centre vents would be roughly equal, but no. The right centre vent blows air, but the left centre vent blows nothing. Has anyone else experienced this ?

 

[mbrands]

Thanks Maurice, would the aux blower not show up on the hammer ?
hammer says everything is fine. makes me feel like I'm imagining things..

 

[burrow01]

Hi

Just been out for a blast with the roof down, temp approx 4 celcius - plenty of hot air available

Pete

 

[DavidR]

Check the 30A fuse in the engine bay on the left hand side for the rear blower fan. Mine blew and the interior fan went from strong to weak in a similar way to your description above.

 

[mbrands]

Thanks David, I'll check it out and let you know how I get on. (Provided I manage to locate that fuse, that is)

 

[DavidR]

The fuse is in the squareish plastic box on the passenger side of the engine bay on a RHD car. 3 screws release the cover and the fuses and locations are printed on the inside of the cover.

Good luck!

 

[mbrands]

I finally got round to checking the fuse, unfortunately the fuse was fine, which means the problem lies elsewhere.

I compared it to another 993 and regardless of which setting you are on, the corresponding fan speed on my car on the same setting is always an order of magnitude lower.

I noticed that with the 30A fuse removed, fan speed on 4 and with a/c on, the fan speed is just a trickle until you turn the temperature dial down to 17 in which case the fan speed picks up. I'm sure this helps the process of elimination, but not sufficiently knowledgeable to know what.

 

[mbrands]

Cheers Maurice, any help or guidance is much appreciated.

 

[tomwinton]

Looks like my car might have this too.... so looking forward to hearing the answer!!

 

[mbrands]

Of the four 993s I've recently been in, only one of them had the proper vent speed, which makes me think that it must be a fairly common age related failure.

I also think that some people who have this problem might not realize it, because their car has been like that since they bought it and they have never questioned it because '911s are known for having poor ventilation'.