The other day after driving my car I noticed that my cat smelled very hot, like it was baking the catalyst. Today I put the car up on jack stands and disconnected the air pump hose from the cat, started the car and let it idle. There was no air at all coming out of the air pump hose. My understanding is that below 3250 rpm there should be air coming out of the hose even if it is idling. So I have an air pump problem.

This is what I check to diagnose the air pump, according to the FSM.

1. I disconnected the air pump hose from the check valve by the cat, started the car and revved it to 2000 rmp and check to see it any exhaust gas was coming through the check valve. NONE check valve is working.

2. Check to see if the clutch on the air pump was working by watching the pulley turn below 3250 rpm and stop above. YES it is working running below 3250 rpm and then stops turning when revving the engine above 3250 rpm.

3. Check the continuity of the wiring harness on the air pump with a voltmeter. YES the continuity is fine.

4. Check to see if the relay for the air pump is working by hearing it click when I turn the ignition to the on position and back off. YES the relay is click.

5. Disconnected the intake hose to the air pump to see if it was sucking or blowing air. It was definitely not blowing and seamed to be sucking air.

There are many other tests to do in the FSM some of which I don't have the right tools to do. I have search and many I just find mention that if the pulley on the air pump stops turn it is done. So does anyone have any ideas as to why my air pump has no air coming out at its connection to the cat?

 

I would check your Air Control Valve and make sure its workin right. Let me know if you need one I have one that only has about 1000 miles on it if not less.

 

So what is the best way for me to teat the Air Control Valve? The FSM states to hook up the Engine Signal Monitor Adapter Harness (which I do not have) to the ECU and then while the car is idling short terminal 4N to see if it causes rough idling. Is there another way to test the ACV without this harness? The FSM also mentions hooking up the ACV to a vacuum pump; does this test it for the same problem?