Holden Commodore Pricing and Specs

There are literally hundreds of things that can cause a check-engine light in a modern, computer-controlled car. A problem with the ignition, fuel system, emissions-control system, air-intake, lubrication, cooling and much, much more can cause this light to illuminate.

The best way to proceed is to have the vehicle electronically scanned. That way, the computer can tell the mechanic where the problem is and, hopefully, precisely what’s causing the check-engine light to flicker on.

For the record, however, a common fault with the V6 engine in this series of Commodores is a stretched timing chain that the computer interprets as incorrect valve timing (which it is). Plenty of owners of this model have discovered this as the cause of their check-engine light.

The first thing to do is make sure your battery is earthed properly and all the relevant electrical contacts are tight and clean. Low voltage or a poor connection can easily cause the problems you're seeing, especially if they've all occurred more or less at the same time.

The next thing is to have the vehicle electronically scanned. That will tell you what faults the on-board computer has spotted, and you can then tackle them logically instead of replacing parts that don't fix the actual problem. The rough running could be anything from a dud oxygen sensor to a fuel-injection problem and lots in between.

I would suspect the heating and air-conditioning problems are separate to the engine's poor running, but anything's possible when a car's electronics start playing up.

It's good news. Your car is indeed compatible with E10 fuel which means you can use the slightly cheaper fuel without risking damage to your vehicle. The car should also run exactly the same as it does on normal unleaded petrol, although you may find you use slightly more fuel per 100km. This should, however, be more than offset by the savings you'll make at the pump.