CHT sensor extension, Curious, does it work? Who uses one? Options

[malcolm2]

I want to cover all my bases here. I have purchased the new GB CHT sensor from 914Rubber to try.

So, I think I will buy a spacer from Brad Mayeur to have the option. From what he says it should:

"Porsche 914/4 Cylinder Head Temperature Sensor Extension.

This little device slows down the heating of the sensor and improves warm up drivability."

I do have "warm up drivability" problems = Low idle RPM until the VDO CHT hits about 250*F. So it seems like my problems don't need the warm up to slow down, it needs to SPEED UP. (IMG:style_emoticons/default/WTF.gif)

914LTD.com





Also found on RATWELL (scroll down to WORKAROUNDS)http://www.ratwell.com/technical/TempSensorII.html#parts

[DRPHIL914]

i have dealt with same issue with my 2.0 d-jet that BeatNavy has described - the issue of the hot start idle too low when restarting the car after being warmed up but off lfor a short run into the store or something of that sort. -
I did get a pot(potentiometer) that was a 0-1kohm that I put in line with the CHT circuit and was able to adjust that to a point where it added enough resistance that this was almost eliminated. but since I replaced the CHT with a new one I had laying around this seemed a lot less and I removed it - I might put it back, because the problem while there isn't as bad with this CHT - you can fool around with other things to lean out the A/F on start up and idle but I don't think that is the way to go .
anyway its not hard to put together a variable resistor in line with the CHT- wondering what you think of this Mr. Anders.... (IMG:style_emoticons/default/popcorn[1].gif)

[pbanders]

i have dealt with same issue with my 2.0 d-jet that BeatNavy has described - the issue of the hot start idle too low when restarting the car after being warmed up but off lfor a short run into the store or something of that sort. -
I did get a pot(potentiometer) that was a 0-1kohm that I put in line with the CHT circuit and was able to adjust that to a point where it added enough resistance that this was almost eliminated. but since I replaced the CHT with a new one I had laying around this seemed a lot less and I removed it - I might put it back, because the problem while there isn't as bad with this CHT - you can fool around with other things to lean out the A/F on start up and idle but I don't think that is the way to go .
anyway its not hard to put together a variable resistor in line with the CHT- wondering what you think of this Mr. Anders.... (IMG:style_emoticons/default/popcorn[1].gif)

EDITED response: This is what I get when I post too late at night and after my third glass of wine. The effect of CHT resistance on mixture is the higher the resistance, the richer the mixture. If you ADD resistance inline to the CHT, you're just going to make the mixture even richer and make it worse! What you want to do is add resistance in parallel to the CHT, which will have the effect of LOWERING the resistance the ECU sees, and making the mixture leaner.

I'll put up a circuit for how to make a switchbox to do this using a potentiometer and a DPDT switch.