924Board.org

[Josh]

just a simple question, is there a difference between a 924 and a 931 (82 model) TPS ? as i have a 931, and after reading something on the net it seams that the previous owner could have gotten a replacement 924 TPS ,possibly by mistake?
_________________
Porsche 924 turbo 82
Alfa gtv 2L 83 (sold)
Suzuki SJ410 (sold)
three awesome cars and still under the age of 21

[juha_teuvonnen]

IIRC the 931 came equipped with CIS, so it' wont have a true TPS (throttle position sensor, i.e. a potentiometer that varies the resistance based on the throttle). The 931 S2 had a few microswitches (3 IIRC) that the DITC used to determine that the trottle is open at a particular angle. I am unsure as to the interchangeability of these switches, my gut feeling is that so long as they open and close at the correct angles they should work.

[Josh]

That does clear it up, mine should work fine then

Thanks a lot! appreciate the info!
_________________
Porsche 924 turbo 82
Alfa gtv 2L 83 (sold)
Suzuki SJ410 (sold)
three awesome cars and still under the age of 21

[ideola]

[juha_teuvonnen]

OP, is your throttle body oval or round? I assumed that someone downgraded your s2 throttle body (round) to s1 (oval), because there's no way to use the NA switches with 931 S2 round throttle body that I can think of.

[ideola]

[juha_teuvonnen]

[ideola]

While I realize the S2-to-S1 conversion isn't impossible -- and I agree, it's not rocket science -- the reality is that most modifications made are hack jobs because the PO doesn't have the time, inclination or common sense to do the job properly. Properly executed retrogrades like you describe are extremely rare.

The S2-to-S1 conversion is one I have never personally witnessed on a running car or otherwise...which is something of a statement considering the number of 931s I've worked on, sold, and parted out. Also, considering the OP is in South Africa, where 931's are relatively scarce, I find it hard to believe someone would have gone to that trouble...finding all of the correct parts locally would be quite a challenge.

It's probably much more likely that a previous owner got a replacement TPS from a 924S (2.5L motor), which uses the same round throttle body casting as the S2 931, and has a very similar (but different) TPS.

Suppliers who don't specialize in the 924 very frequently make these kinds of mistakes, so it would not be surprising at all if the PO called up a local South African auto parts store, asked for a TPS, and got one for the 2.5L motor.
_________________
erstwhile owner of just about every 924 variant ever made

[juha_teuvonnen]