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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
Posts: 3,860
Might I suggest you purchase the following Bosch Fuel Injection Management book
Pelican Parts - Product Information: BK-112910B
A must-have for understanding CIS fuel injection. If you're not familiar, understand that when you hear the word "fuel pressure", with these cars (or any CIS system) there are several different pressures: System pressure, which is basically the pressure delivered by the pumps and controlled by a pressure regulator internal in the fuel head (easily removed and shimmed to fine tune the pressure). That system pressure is further modulated by the WUR, to provide what's called control pressures. You have a cold start control pressure, which will be lower than the fully warmed up control pressure. These control pressures are what dictate your mixture at cold, warm, and cruise. So it's a combination of system and control pressures that must be correctly set. Unfortunately, the control pressures aren't adjustable (not conventionally, anyway) unless you have an adjustable WUR.

You'll need to obtain the proper gauge setup for testing both system and control pressures.
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 06-21-2013, 11:22 AM
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