[V8] Flashing CAT light

Buchholz, Steven Steven.Buchholz at kla-tencor.com
Tue Aug 24 15:01:09 EDT 2004

... in my best Ed McMahon voice ... you are correct sir!

The CAT light on the IC is completely independent from the ECU.  When I got
#344 the light was on ... I fixed it by tightening up the sensor in the
right side cat ... not a whit of a problem since.  #2 has had a flashing CAT
light since I bought it.  Since it flashes when the engine is cold I haven't
been too worried about it.  There's a connector in the passenger compartment
in the front passenger footwell (LHD) tranny tunnel area where the temp
sensor attaches.  I'm going to disconnect that connector and see what it
takes to turn the light off ... of course, here in California you've got to
have the light come on for a few seconds when the car is started, so I can't
just pull the bulb.  

I thought I'd give an update on my cat situation ... I picked up a couple of
the Catco universal units from Summit Racing as was suggested from the list
... $50 each.  As a part of preparing for the V8 conversion on the Avant I
picked up an exhaust crossover and set of cats ... when I pulled the
crossover from the front I found that the cats were hollow ... and I don't
think it was anything that anyone did deliberately.  It makes me wonder if
there's anything in the cats for either of my cars ... 

Steve B
San Jose, CA (USA)
> Correct me if I'm wrong,
>    I believe that the cat light has no connection to the ecu - maby on
> later cars but I don't think the 90's had a connection.  I 
> believe all the
> circuit consisted of was the light, controller, and sensor.  
> The light and
> sensor are self explanatory, the controller was needed to sense ground
> faults and the like.  Again, I could be wrong,

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