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Warrens69GMC · 02-28-2017, 11:19 PM

sounds like a vacuum leak. When you are on the gas vacuum is lower, hence it running "better". With cruising or idling, vacuum could be its highest, giving the leak somewhere to go and causing the bucking.

02-28-2017, 11:19 PM	#2
Warrens69GMC Registered User Join Date: Jan 2003 Location: Safford,AZ Posts: 3,613	Re: 305 engine issues sounds like a vacuum leak. When you are on the gas vacuum is lower, hence it running "better". With cruising or idling, vacuum could be its highest, giving the leak somewhere to go and causing the bucking.