Should I add this to my fuel at the end of the season and leave it until the spring, or would it have adverse effects to internals within the fuel tank?

It would be best to use while routinely driving the vehicle.

Can i use this product on a base 2013 mini countryman?

Yes, you can.

Can this product be used on my 2006 E350?

Yes, you can.

Hola Este product, es Bueno para dos Mercedes Benz ML550 2013 y E320 2004

Yes, this product is suitable for both Mercedes models.

Hey guys, would you recommend I use this or DI Jectron for my b8.5 Audi allroad?

Di Jectron would be better suited for your application.

For modern DI BMWs, should I be using this, or DI Jectron? (What's the difference?) This says for port injected...

You should use the DI version for your DI engine. Each formula is optimized for each type of injector.

Is this the proper cleaner for the b7 Audi s4 4.2 V8 or should I be buying the DI -Jectron version?

The standard 4.2 used in the S4 is a port injected engine. This fuel injection cleaner is the appropriate option for your vehicle.

I had a valve cover gasket replacement recently and a day after my bmw 525i 2007 started jerking when I accelerate at a stoplight. I put some of this in the tank and it stopped do you think the cause was dirty fuel injectors ??

Yes, it's possible as this cleaner is specifically designed to clean fuel injectors.

How often can this be used? You note in the description "at every refuling", but the can and the LiquiMoly site says every 1,200 miles. Which is correct??

It can be used as often as you would like but 1,200 to 1,500 miles would be a good interval.

Is this product safe for use on a 2009 Mercedes C300 (W204) and a 2017 Audi Q5 2.0T ? Also, how does this product differ from DI Jectron Fuel Injection Cleaner (300ml) - Liqui Moly 22076? Is one preferred over the other?

Yes, I recommend this Jectron Fuel Injection Cleaner for your 2009 Mercedes C300 (W204) and 2017 Audi Q5 2.0T.