× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network
Re: GM Fuel Pump Diagnosis
Posted to Technical Discussion Forum on 12/27/2018 3 Replies

It bothers me your rear 02 sensors are over 800 mv while your fuel trim is screaming lean.

Can you verify proper front AFR sensor operation? Add fuel/spray/propane and cause a vacuum leak to exercise them and monitor performance.

Also for your max rpm your... Login to read more.

3 Replies Received (View Replies)