EGR Tube - Diagnosing Poor Performance/Mileage
84amcjeep03SEPTEMBER 1984 000 278
1983-84 CJ/SCRAMBLER 1984 CHEROKEE/ WAGONEER 70 SERIES
20E
ENGINE Attention: Workshop
ENGINE PERFORMANCE DIAGNOSIS
Information
As a reminder, when diagnosing a 2.46L engine in one of the subject models for poor performance, low fuel mileage, and/or difficult hot starting, don't forget to also check the EGR tube-to-exhaust manifold flange gasket for complete sealing.
Checking procedure is as follows:
1. Disconnect EGR valve tube nut from intake manifold.
2. Remove tube flange bolts from exhaust manifold and remove tube and flange gasket. Discard flange gasket.
3. Clean gasket surface of tube flange. Remove any burrs on gasket surface with emery cloth.
4. Check flatness of tube flange gasket surface with straightedge and feeler gauge. It is important that flange gasket surface flatness be checked whenever the tube is removed for service. Replace tube if 0.50 mm (0.020 in) feeler gauge can be inserted between straightedge and gasket surface at center or ends of flange.
5. Clean tube flange gasket surface on exhaust manifold. Remove any burrs with emery cloth.
6. Loosely connect EGR valve tube nut to intake manifold and flange bolts to exhaust manifold. Be sure to use new gasket between tube flange and exhaust manifold.
7. Tighten tube nut to 41 N-m (30 ft-lbs) torque.
8. Tighten tube flange bolts to 19 N-m (14 ft-lbs) torque.
NOTE: This is a revised set-to torque for the flange bolts. Record the following new set-to and service recheck torques on Page B-3 of the M.R. 244 and Page B-49 of the M.R. 252.
Set-to torque: 19 N-m (14 ft-lbs)
Service Recheck Torque: 14-24 N-m (10-18 ft-lbs)
Filing Instructions
Record this I.S. Note on Pages B-3 and B-16 of the M.R. 244 and Pages B-49 and B-84 of the M.R. 252 and file it in your M.R. 171 binder.