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Discussion Starter #1
Ever since I put an ipd ECU in my '96 850Turbo, I get periodic hesitation/missing when I'm under full throttle (floorboarding the accel). Usually this is around 65mph after a standing start, or sometimes when I pull out to pass, at 65 to 70. If I let off the gas a tad, the hesitation goes away. I always run 92Octane from Chevron and didn't see this b4 the upgrade.<P>Ideas? Thanks for y'all's help!<P>
 

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Could be a lean condition or the knock sensor retarding the timing. If you've never replaced the fuel filter on a 30k+ car, I would start there. If that's not a problem, try some 104+ octane booster (one bottle for about 1/4 tank worth) and see if it still happens. If the problem goes away with the octane booster, you may be getting some pre-ignition under heavy throttle. Its common for denotation to happen more while in higher gears, as there is a higher effective load on the engine. Hope this gives you a place to start.<P>
 

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Thanks Lee. I added some Octane104, but to a full tank, and I notice it still occured. I did notice that the local Chevron station that I use has '90' posted instead of the '92' that they used to advertise. That could be an issue I suppose.<P>Is the timing adjustable on this motor? Could this be moisture related w/the distributor? Could it be the O2 Sensors? Vaccuum leaks? I'm reaching. It only does it under full wide open throttle, and if I lift just an 1/8th or so, it goes away.<P>Anyway, gotta figure this out... driving me crazy. <IMG SRC="http://www.swedespeed.com/ubb/smile.gif"><p>[This message has been edited by javadoc (edited 08-14-2002).]
 
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