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For unmodified turbo owners -- is this why your car sometimes feels slower than other times? S40-V40 99

Just saw this on the Subaru Impreza BBS, which may help to explain why turbo models with the stock ECU sometimes seem to fly, and other times don't seem as quick. Food for thought .... and it does match what happens when I drive my 99 2.0T (160hp). Now what's TMEs / IPD's number?

"A problem that's troubled Impreza owners for years is that after a period of driving at steady, low RPM and light throttle, booting the throttle to overtake only gives about half boost, and you need to lift off a bit and reapply to get full boost, but why does this occur???

The answer is that the ECU has an algorithm to help the car through emission and noise tests. The ECU designers have programmed it to know that if it is held on a steady throttle for between x and y seconds, then it is a noise test and only to give los boost. Clever or what?

The story was related to me by a member who was at a lecture, held by some of the worlds OE ECU mappers. Apparantly they all do it, not just Subaru."







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New For unmodified turbo owners -- is this why your car sometimes feels slower than other times? [S40-V40][99]
posted by  someone claiming to be Craig  on Thu Nov 16 22:31 CST 2000 >


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