Catalytic Converter - Checking/Replacement Procedure
85VW1Applies To Water Cooled
All
Group
26
Subject Catalytic Converter Assembly
Part Identifier 2663 2673 2686
Key Points
Checking/replacement procedure
(Supercedes P-Circular, Group 26,
Numbers : 78-01, 80-06 )
C
Number
85-03
July 25, 1985
Determining need for converter replacement
Converter replacement can become necessary if the ceramic insert loosens.
If exhaust "rattles"
- check that exhaust flanges are tight
- check heat shields for proper mounting
Note 1985 models have spotwelded heat shields Earlier models have bolted heat shields.
If "rattle" was not due to loose exhaust system or loose heat shield, converter may have failed.
If exhaust system is tight, - remove catalytic converter
- look through both flange openings against light
Note Visual inspection of ceramic insert is not possible on 1985 model converters.
If ceramic insert appears broken or melted as shown in both pictures, converter has failed..
If ceramic insert appears OK, check if ceramic insert is firmly seated in converter housing.
Check as follows:
- while holding converter vertically, firmly tap flange onto solid wood from a distance of 20 cm (8 in)
- turn converter over and firmly tap other flange as before
If no knocking sound converter is OK
If no movement of the ceramic insert, converter is OK
If light knocking sound is heard inside converter ceramic insert is loose and converter has failed.
CAUTION
Avoid the following conditions on vehicles equipped with catalytic converters.
^ usage of leaded gasoline
^ turning off the engine with the vehicle in motion
^ excessive prolonged cranking with an intermittent firing of a flooded engine
^ prolonged operation under load with a misfiring engine
^ prolonged idling (excess of 5 min) on the high step of the fast idle cam (carburetor equipped vehicles)