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**Wrenchbender Ret** · 07-12-2019, 09:38 PM

The ASM is a switch that only allows the vacuum advance to work in high gear with an auto trans. It is an early emission control device & is best left bypassed.

07-12-2019, 09:38 PM	#12
Wrenchbender Ret Registered User Join Date: Oct 2005 Location: Overland Park, Ks. Posts: 5,190	Re: 71 blazer - green ground wire The ASM is a switch that only allows the vacuum advance to work in high gear with an auto trans. It is an early emission control device & is best left bypassed.