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Airflow Plate resistance Posted by Gary Stottler [Email] ![]() ![]() In Reply to: I made sure that..., BAAB ![]() ![]() |
Baab,
What you are observing seems to be correct - when the fuel pump is running, the Control Pressure will be pushing down on the top of the plunger which will create resistance to the airflow plate rising. When the engine is cold the Control Pressure is less, thus the airflow plate rises higher, the fuel distributor meters more fuel, and you get a richer mixture. All this assumes two things:
1) that there is nowhere else the air can flow into the intake valves without going through the air box and past the airflow plate, and,
2) that the fuel pressure is correct. Since you say the engine runs OK if you raise the plate manually, that suggests that the Line Pressure is probably not too far off - at least there's enough to crack open the injectors. The Control Pressure has to be tested using the fuel pressure guage set shown in the manual - Control Pressure will be a function of engine run time and engine temperature and is governed by the Control Pressure Regulator, also known as the Warmup Regulator (metal box bolted to the thermostat housing).
Hope that helps!
Gary
posted by 173.87.15...
_______________________________________ Gary Stottler
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