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BFL13's avatar
BFL13
Explorer II
Jul 20, 2021

Air Pump to Cat 1991 Ford 460 Question

Couple years ago, plugged cat removed and replaced with pipe. Garage suggested remove the air pump as well. I said leave it in, thinking if I had to put a real cat back in, but fairly clueless on the topic. Anyway it's still there.

Now I am getting the engine light after driving at highway speed for about two hours and then slow down. If I turn off the ignition and restart the light does not come back on.

I gather this light is to do with air emissions, and there is an oxygen sensor involved. Is that associated with the air pump to the cat? Should I have that air pump removed and maybe the oxygen sensor with it, (if it is with it) or does it matter?

Seems like everything is running well since the cat was removed so I am not sure if I need to worry about all this or not. Thanks in advance!
Class C
  • DRTDEVL's avatar
    DRTDEVL
    Explorer
    Jul 21, 2021
    klutchdust wrote:
    rjstractor wrote:
    If it's running good I wouldn't be too inclined to mess with it much as long as you don't have emission testing or inspections. It's pre-OBD2 so taking it to an auto parts store for a free code reading won't help. Checking the code involves some combination of jumping terminals and counting flashes- do some research on the internet on how to do this or get your hands on a repair manual.


    What year vehicle are we talking about and why can't a reader be plugged in. Counting flashes sounds like a old vehicle.


    The answer to your question is literally in the title of his post.
  • BFL13's avatar
    BFL13
    Explorer II
    Jul 21, 2021
    rjstractor wrote:
    If it's running good I wouldn't be too inclined to mess with it much as long as you don't have emission testing or inspections. It's pre-OBD2 so taking it to an auto parts store for a free code reading won't help. Checking the code involves some combination of jumping terminals and counting flashes- do some research on the internet on how to do this or get your hands on a repair manual.


    Thanks, took your advice and went to Google and found a whole bunch of info on this, so now I have a better idea what could be happening and what I should do about it.
  • klutchdust's avatar
    klutchdust
    Explorer II
    Jul 21, 2021
    rjstractor wrote:
    If it's running good I wouldn't be too inclined to mess with it much as long as you don't have emission testing or inspections. It's pre-OBD2 so taking it to an auto parts store for a free code reading won't help. Checking the code involves some combination of jumping terminals and counting flashes- do some research on the internet on how to do this or get your hands on a repair manual.


    What year vehicle are we talking about and why can't a reader be plugged in. Counting flashes sounds like a old vehicle.
  • rjstractor's avatar
    rjstractor
    Nomad
    Jul 21, 2021
    If it's running good I wouldn't be too inclined to mess with it much as long as you don't have emission testing or inspections. It's pre-OBD2 so taking it to an auto parts store for a free code reading won't help. Checking the code involves some combination of jumping terminals and counting flashes- do some research on the internet on how to do this or get your hands on a repair manual.

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