Porschedoc,

I have a 2000 Boxster S with tiptronic gearbox. The revs are hunting when in 4th and 5th gearwith the enginefluctuating between 1600 and 2000rpm and the idle speed sometimes reaches 1100rpm when I come to a stop and take out of gear after a run. The engine runs fine when pushed through the range in neutral with no blips. There is no engine management warning light but the Porsche garage did find a fault reading on right hand side timing. I have since checked the alignment of cams and adjusted with the aid of setting tool,they were slightly out after head gasket change, but I still have problem. Could this be the variable cam solenoid on its way out, a dodgy cam sensor or even a faulty gearbox?.

By the waythanks for your previous advice on dodgy fuel pump,I changed the old one and it has been running fine, with the exception of the fault detailed above, since.

 

Start with something really easy and clean your MAF first and double check for any intake leaks. When did the hunting start? Was it immediately after the head gasket work?

 

PorscheDoc, Thanks for quick reply. Head gaskets changed 5 months ago whilst investigating cause of oil in coolant; turned out to be cracked gearbox cooler. Problem with hunting started about a month ago and gradually getting worse, I noticed today that it is also hunting whilst in gear at idle between 600 and 900RPM. Checked air and vacuum system yesterday for leaks but none found. Also MAF removed and found to be clean, apparently it was changed by previous owner about 3,000km ago. Any ideas?. Oh and Happy New Year.