
1994 Chevrolet C3500 Cheyenne 7.4L Excessive Emissions, Poor Idle Quality, Poor Fuel Economy, MIL Lamp on
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...
FIX posted 4/25/2015
![]()
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 (View Replies)27 Replies Received(Hide Replies)27 Replies Received
|
Message Closed w/FIX
|
VIN | 1GBKC34N4R |
Engine | 7.4 L / 8 cyl / GAS |
Trans | 4-speed Automatic (Electronic) |
Delivery | Fuel Injection / TBI |
Emissions | OBD1 CALIFORNIA |
Symptoms | Excessive Emissions, Poor Idle Quality, Poor Fuel Economy, MIL Lamp On |
Occurs | Always, Worse When Cold |
Trouble Codes
33 | Map sensor high |
45 | Exhaust rich |
Message Closed w/FIX
Vehicle Data
1994 Chevrolet C3500 Cheyenne
VIN | 1GBKC34N4R |
Engine | 7.4 L / 8 cyl / GAS |
Trans | 4-speed Automatic (Electronic) |
Delivery | Fuel Injection / TBI |
Emissions | OBD1 CALIFORNIA |
Symptoms | Excessive Emissions, Poor Idle Quality, Poor Fuel Economy, MIL Lamp On |
Occurs | Always, Worse When Cold |
Trouble Codes
33 | Map sensor high |
45 | Exhaust rich |