cookceramics

I drove about 5k's to the 711 on sunday night and noticed a ticking from the engine at idle. Operating temp was up and rpm redline had risen as normal on tacho. The car does about 5000k per annum so it rarely leaves the garage. I drove it very hard on the way home and noticed the noise was gone when i let the engine idle at the front gate.

I want the car in perfect order and I beleive the oil has "gone off", should I dump the oil and filter regardless or keep looking further? Oil only lasts 5000k in my opinion!