1986 280GE, 115k, head rebuilt at 90k.

What would cause the Cat substrate to clog and then fail? Basicly I've had a plugged cat for sometime. Gee, now I know why the engine was losing power and trying to overheat.

Trying to isolate the fault. My thoughts so far are rich running. SOurces: leaking cold start injector, idle set too rich, others...?
What if the EGR valve has failed to the closed position? Would this lack of fresh air prevent a clean burn by the time the mix gets to the cat?

What else?



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S, J.R. Brown
1986 280GE LWB Anthracite
1980 450SEL Champange
1981 Volvo 240DL UPS Brown