1991 GMC R3500 7.4L Excessive Emissions
Truck runs well , fails emissions at idle . With scanner installed and monitoring, perform 2500 rpm test for 30 sec ok, return to idle stays in closed loop for 15 sec then goes open . O2 sensor at .890 fixed system co goes to 2.39 and fails test . I have check...
FIX posted 7/23/2011
iATN Members:
Login to view full TechHelp request Auto Repair Pros: Join iATN to read this TechHelp request Vehicle Owners: Find a nearby iATN member to repair your vehicle 11 Replies Received (View Replies)11 Replies Received (Hide Replies)Related Documents & MediaRelated Documents & Media |
Message Closed
Vehicle Data1991 GMC R3500
|
Message Closed
Vehicle Data
1991 GMC R3500
VIN | 1GTHR33N3M |
Engine | 7.4 L / 8 cyl / GAS |
Trans | 4-speed Automatic (Electronic) |
Delivery | Fuel Injection / TBI |
Emissions | OBDI,CA. EMISSIONS |
Symptoms | Excessive Emissions |
Occurs | Idle |