unstable idlling-stalling im going nuts

[leadfoot6]

My point is that, on the 3rd Gen TB, the TPS cannot be adjusted without moving the point at with the idle switch triggers, since they are integrated into a single unit. For this reason the TPS setting procedure concentrates on the point at which the idle switch triggers rather than min/max resistance across the TPS range, which is only tested to verify that the sensor is working properly. The older 1st/2nd Gen setup was different, the idle switch was on the end of the concertina-shaped idle speed controller and the throttle position sensor was a separate unit.

My concern is that someone reading this thread may assume that tweaking the position of the TPS is a valid way of correcting some gear change behaviour in 3rd Gens, this may well be valid in earlier Magnas or other vehicles where the TPS is separate from the idle switch but is likely to introduce idling problems with the 3rd Gen throttle body setup, as far as I understand it. In most cases the TPS will never need to be adjusted from factory settings, so you're spot on regarding the white paint dot which will be unbroken in most cases.

In a brand new car, certainly, there would be no need to alter the factory TPS setting.

However, over time, all sorts of variables can be introduced that can alter the optimal settings.

Also, if there was only one correct setting the modern day TPS would be made with no adjustment.

Well, up to the TLTW, which is what I am familiar with anyway.

Bottom line: If the car with a factory original setting TPS is misbehaving, there is not much to lose by experimenting with the settings.

It doesn't cost anything, and it is relatively easy to return it to the original setting.

GRH has said that he has put on a new TPS, so the factory original setting is no longer there.

Tip: before "adjusting by feel" with the TPS take a voltage reading as per the workshop manual and write it down.

Use that as the starting point and make very small adjustments , road testing after each change and writing down the new voltage reading at each stage, and if it is ever perceived that no improvements are being made(or the behaviour is worsening), just return the TPS setting to the one written down at the start.

As I mentioned earlier, I have not had the need to adjust mine, but as I have seen first hand witnessing how a qualified transmission mechanic approached a transmission problem on a TR/TS Magna, I am confident that such a method as I witnessed may be transferred to other cars in a similar manner, even if they are not identical(e.g. my Nissan R31).