This. I have exact same symptoms (like we have been discussing before) still. Actually best way to "detect" if car is on that "crappy" mode is to test it with idle, holding throttle very slighty above idle.Mandrake wrote:So I've decided that as well as the spark plug leads being dodgy, its high time I replaced the TPS.
Even when the engine has been otherwise performing perfectly with the swapped ECU and temporarily taped up spark plug leads, one problem has stubbornly persisted for months and has not responded to anything I've done - a big flat spot/hesitation just above idle.
The symptom is that the car will be idling perfectly, but if I tap the throttle just slightly with my foot it will stumble/hesitate and in fact nearly stall, with the indicated rpm dropping way down before it recovers.
It doesn't seem to exhibit this for the first 30 seconds or so after a cold start while the cold start enrichment is still active, but it does it at any other time whether partially or fully warmed up.
While driving its noticeable as a stumble / momentary cut out when accelerating from stationary, and it's sometimes noticeable in 2nd gear on take up from coasting.
If I hold the throttle very slightly above idle the rpm will drop and then start oscillating up and down. From all these symptoms I think I have a TPS with a dead spot in it where the wiper is loosing contact just above the idle position.
When i watch my TPS values on diagnostics, they do look just fine. No skips or anything, but lexia has such a slow update rate that there could be some problems anyway. I already tried to "reposition" my TPS as it's possible to rotate it just a little. This however was long time ago and i had that crappy intake pressure sensor and glogged up ICV. So spraying it up with some electronic cleaner and so could help or not. After TPS sensor only sensors left unchanged on my car are CPS and knock sensor.