Hi I'm driving a 2010 Aurion Pressara for over a year now in Saudi Arabia. I was using the 95 Gasoline since day one. Two weeks I ran into a situation where my fuel was low and I was not able to get 95 Gasoline so i was forced to fill the 91 gasoline. Now Even after, two refills, I feel my car is not driving like it used to. It has a heavier response than before. What do you suggest? 1) Use a Cleaning agent to clean the fuel injectors or 2) Continue using the 95 gasoline and the old 91 residue will go away. or 3) I'm all ears to your suggestions. My Current Mileage is above 25,000 Kms (15625 m) and we only have leaded gasoline here in Saudi Arabia. Applegarth is right. Use quality fuels and you'll find you probably won't need to use injector cleaners. On top of that, you'll probably also find that you get better fuel efficiency too. Another good way to clean out your injectors is to every so often do a nice long drive at max country speeds (eg. 110km/h in WA) for a minimum 30km or so. This does wonders for injectors by blowing away whatever crap is messing up the spray pattern thus bringing up performance and efficiency, plus the engine also gets to burn off any collected soot or sludge/crap etc that's built up. If you aren't able to do the long high speed drives to "burn off the built up crud in the injectors", the next best thing is to avoid CULP 91 (CULP - Crap Unleaded Petrol). BTW, has anyone noticed that ULP 91 has a totally different color to PULP 95 or Vortex 98? Me thinks there's lots of leftover crap from the refinery in ULP 91...... either that, or this must me a local phenomenon in my area. I also wonder if anyone else has noticed something unusual with fuel from Woolies branded petrol stations. These are NOT the Caltex ones, just the pure Woolworths ones. I've been buying fuel from Woolies for a while (not for my aurion, but for a company vehicle which I'm only allowed to put non-premium unleaded into, so I only put in the cheapest n nastiest fuel I can find!), and I've noticed that their unleaded tends to FROTH a lot. I mean actual froth, like bubbles which stays there and doesn't disappear. This is totally different to fuel bubbles. It's almost as if I'm filling the tank with dishwashing liquid, bubbles and all..... I also notice that the company car has been running like a ****bag and I'm betting it's the cheapa$$ fuel I'm putting in it. Either that, or that's how Fords normally are. No offence to any Ford drivers out there. Anyway, bottom line is, if your car gets to do enough long distance or sustained highway speed (100km/h or more) driving every couple of weeks, you probably won't be needing to add injector cleaners to your fuel. This is even with lots of stop/start traffic driving between the long drives. Cheers, BB