Hi guys,

I am interested in the views of technical experts/engine builders/tuners on the following products.

STP fuel injector cleaner, my family always run it through there cars every 10k miles or so (we are high mileage drivers so that's every 3 months ish) We are using it in all manor of cars, older with high mileage (150k+) or newer and lower mileage (20k ish miles) It *seems* from a drivers perspective to smooth out the idle a little and just keep the car pulling very smoothly. However I don't know if standard fuel from good stations really gums up your injectors or if it isn't necessary?

Engine flush: The type that u put into your engine oil, run the car for 10-15 mins and then drain along with the oil when u oil change ur car.

All the engines that I have taken to pieces (my old rst etc) were very clean inside however now that I run a car that someone else services (BMW look after the M3 to keep the service history up) I don't think it gets flushed before the oil is drained. Are either of these products really of any benefit?

Cheers!

Steven RW