I know that these can be problematic for the 4.7. I don’t have any problems now and have about 145K miles.

Is there some kind of preventative way to determine if the pump is going out? If I take the manifold off is there a way to check the status of the filter in the pump that seems to cause the problem. Or is this one of those where you wait till it’s broken type of things?

I’m not interested in the bypass kit, so if things need changing I would just get the OEM part and do the replacement myself. I just don’t want to be on the road somewhere and be stuck in limp mode if it goes out.

 

I didn't get introduced to the secondary air pumps until we got our GX460, as our '04 is too old to have one. The 460 guys recommend replacing the foam filter that breaks down and gets sucked in and destroys the pumps with a unifilter, which I have now done on mine as a preventative measure.

You can find the details in this thread, I'm assuming the pumps are pretty well the same and the same fix would apply:

https://www.clublexus.com/forums/gx-...ke-pump-3.html

 

I looked into the UNI filters and it looks like they don’t exist for the GX470. I am wondering if I will have to replace the whole unit, which is not cheap