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1994 Chevrolet C3500 Cheyenne 7.4L Excessive Emissions, Poor Idle Quality, Poor Fuel Economy, MIL Lamp on
Posted to GM Driveability on 4/10/2015 27 Replies

Ok this one has me. It came in for a intermittent rough run with CEL on. Has codes 33 MAP high and 45 rich exhaust so I started with the Map found it reading 3.6 volts @ idle. Manifold vacuum was low @ 14" repaired a small leak at #6&8 manifold gasket now I ha...

27 Replies Received (View Replies)

  Related Documents & Media  1994 Chevrolet C3500 Cheyenne

 
Message Closed w/FIX

car Vehicle Data

1994 Chevrolet C3500 Cheyenne

VIN 1GBKC34N4R
Engine7.4 L / 8 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFuel Injection / TBI
EmissionsOBD1 CALIFORNIA
SymptomsExcessive Emissions, Poor Idle Quality, Poor Fuel Economy, MIL Lamp On
OccursAlways, Worse When Cold

Trouble Codes

33Map sensor high
45Exhaust rich
Message Closed w/FIX

car Vehicle Data

1994 Chevrolet C3500 Cheyenne

VIN 1GBKC34N4R
Engine7.4 L / 8 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFuel Injection / TBI
EmissionsOBD1 CALIFORNIA
SymptomsExcessive Emissions, Poor Idle Quality, Poor Fuel Economy, MIL Lamp On
OccursAlways, Worse When Cold

Trouble Codes

33Map sensor high
45Exhaust rich