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GMC Truck
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1986
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C 2500 Truck 2WD V8-379 6.2L DSL VIN J FI
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Description and Operation
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Vacuum Modulator Valve (VMV)
Vacuum Modulator Valve (VMV)
The vacuum modulator valve is installed between the Transmission Converter Clutch (
TCC
)
solenoid
and the
EGR
/
EPR valves
on V6 and V8 diesel engines. The VMV limits the vacuum signal to the EGR/EPR valves to 13 inches Hg.