Hi

I have a 2003 Mazda 6 Lux Sports Hatch with 130,000km - 4cyl 2.5L Manual

For the last few months i have been having a surging/misfiring issue at low rpm (is fine once i get over 1500-1800). This occurs in all gears and is more prevalent when aircon is on.

I have had it in the shop and had the following done;

* Full electrical test
* Replaces spark plugs with NKG Iridium ones
* Had spark leads replaced
* Put through injector cleaner
* Replaced Oil, Fuel filter and air filter

I have now been running 98ron fuel rather than the 95ron recommended for my car as it is less noticeable with this fuel. Once i replaced leads it was good for about a month before starting the issue again and then i replaced spark plugs - which also solved the problem for about a month. I have already spend quite a few $$ getting Mazda and other mechanics looking at it.

Has anyone had a similar issue or have any suggestions in regards to a solution?

Thanks