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

[BeatNavy]

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)

Not sure what you're saying here. What the spacer does is increase the amount of time for the CHT to go from cold/cool (when the ECU richens the mixture to compensate for cold engine) to warm/hot when the engine can run effectively on a leaner mixture. If you're having low idle while cool I'd suspect something else, like an AAR that's not operating properly.

I use one of Brad's spacers. My cold engine driving is good. The possible downside, which is probably attributable to or at least aggravated by the spacer, is the warm-start over rich condition. If I stop for an errand and then restart the car, the engine idles low to the point of almost dying for about 30 seconds. It's caused by the CHT cooling down faster than the engine and running too-rich. Funny, though, my A/F ratios don't look especially rich during the period that occurs. I'm looking at other potential root causes or ways to mitigate. I may remove the spacer for a few weeks to see how things run without it.

[pbanders]

The possible downside, which is probably attributable to or at least aggravated by the spacer, is the warm-start over rich condition. If I stop for an errand and then restart the car, the engine idles low to the point of almost dying for about 30 seconds. It's caused by the CHT cooling down faster than the engine and running too-rich. Funny, though, my A/F ratios don't look especially rich during the period that occurs. I'm looking at other potential root causes or ways to mitigate. I may remove the spacer for a few weeks to see how things run without it.

I didn't see your comment until I made mine, looks like we both came to the same conclusion. Try the method of hot starting that I suggested and see if it helps. If you come up with another explanation for this behavior and a fix make sure to post it.