Checking rich/lean conditions

From: (rwynkoop at

>I think my catalytic converter has crapped out on me! Once the engine 
>warms up I get no powerand had to coast home from work today. I hear a 
>loud hissing noise coming from the converter. I just had new mufflers and 
>tailpipes put on last year. I just put a new cerb on this weekend. Has 
>anyone else had their converter go bad?? Stock L69, 97,000 miles, new 
>plugs, new coil, cap, rotor, plug wires.  

Sounds like a converter problem. Your carb may be running too rich and caused 
the cat to plug (or it was on its way out already.) If you car is computer 
controlled you can find out what the computer is trying to do the mixture by 
hooking a 6cy dwell meter up to a green pigtail connection just in front of the 
carb. If the idle bleed screws are adjusted ok you should get a 30 deg reading.

 If this value is lower then it means your carb is lean. If this value is 
high (50-60 deg) then your carb is running rich.

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