I have a few niggles that I would like to sort on my late 2003 cayenne TT - 108k miles.

1) PSM and air suspenion light keep coming on. Will go out for a while but come back on again at some point. Run diag and error code is for steering sensor. Have done calibration by turning steering wheel and driving straight forward. This clears errors off dash straight away but usually come back at some point in the journey.

Thought it was a defective battery so put in new one in and still the same errors. Checked the alternator and it is charging well.

Recently put 4 new tyres on - 275/45/20 instead of '40' profile but think the errors were prior to this. Also, fit 1" spacers on the rear for aesthetics.

Could this be MAF related? I have a CAI. I remember I forgot to re-fit the MAF when fitting the CAI and it threw up the same errors but it also did not show the gear selection (this is currently working fine). Engine running great.

2. Starter turns quite slowly and sometimes requires 2nd turn. Seems to be worse when engine and ambient temp is warm. Ruled out battery as it's new and the issue hasn't improved compared to old battery.

3. Front diff bearings went so had the diff refurbed. Grinding noise completely gone but I can still have a faint high pitched whine above 80mph that I can 'play with' by going on and off the accelerator. Company who did the work is very reputable. The mechanic that worked on the diff said they set the tolerances slightly looser than OEM as in their opinion it was too tight when reassembled.

4. Very light ticking at idle that appears to be coming from under drivers (uk RHD car) side door. Not coming from engine bay.

5. Since getting warmer for summer I have noticed that the suspension squeaks when going over speed humps.

6. Right hand blower vents won't blow warm.

Any pointers appreciated. Love the car.... Love it more when above annoyances are eradicated.