Just returned from ANOTHER trip to the chaotic northeast (told you #5939 was becoming a fixture on I-95) and checked last week's messages. So many controversies... My thoughts on R134 are already well known (pumped just fine yesterday), but this was a new one: combined heat of radiator and condensor kept coolant above 220 degree mark until dark. That, combined with missing fresh air hose, allowed pre-detonation to start creeping in somewhere between Fredericksburg and Richmond (remember: I'm timed 10 degrees BTC per Renault specs). Since I still had 3/4 tank of gas, just bought a bottle of octane boost. Of course cleared up immediately. Refilled with 93 octane in Roanoke Rapids for continued quiet running. At Fayetteville went back to 89 (my usual). I know octane boost is slightly different formulation than injector cleaner, but FWIW my car not only survived 400 miles with an additive in its tank but started just fine this morning to come to work. My prefered use for these cleaners remains straight down the intake. Won't remove carbon deposits, but will burn off light weight soot, oil, or anything else gumming up the works from the topside. I call it "making smoke". Looks just like this http://www.delorean.co.uk/pictures/DCP02268_1.jpg I think Martin G would agree, car runs better afterwards. BTW Louie: went grocery shopping with mechanic buddy while in DC. You should try squeezing them in when parcel shelf is full of traveling crap that no longer fits under hood (it all fit when I left the house...). Packed him in as you said, then STILL had to drive with a bag under MY legs. Imminently practical transportation. Bill Robertson #5939 Bill Robertson #5939