Hello Italy, from France.

I have a very similar car without the turbo. For me, all changes are very good. BUT, if I am accelerating hard, 4th to 5th has a problem. It switches between 4th/5th/4th, until I release the accelerator and the 5th engages.

I call this "hunting". The gearbox hunts for 5th, it traps 5th but 5th escapes until it is trapped again.

Everything on mine has been changed - rebuilt gearbox, switches, HGS controller, electrical connections etc.

The only thing that has not need changed is the throttle position sensor (TPS) - the plug/switch and cable assembly you see in the attached image.

I have measured the resistance of this switch and the results are not a stable as those from another switch. So, one day I shall change the switch but it is not a high priority for me.

I have had this problem for many years, both before and after the gearbox rebuild and a major engine overhaul in 1997. Basically, it has done this since the late 1990s when I first noticed it.

Sorry I cannot be more helpful to you.

Good luck.

RayH

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