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I am on my 3rd secondary air injection pump

I have just put in my third secondary air injection pump into a 2001 GMC Jimmy in less than a year. They keep getting water in them and I do not know why? I think it was changed once before I bought it because the intake hose on the pump had been disconnected and moved up to the firewall. Is there some other way that water could be getting into this pump from the exhaust side of things? I have been reading about some other parts for this system that can go bad like a valve or something like that but I do not know if they could contribute to my problem or not. I would really appreciate some insight because this is getting old fast. Thank you for your help

Air contains water vapor. It always has, and it always will.

One of the byproducts of combustion is water vapor. More water.

“Secondary air injection pump.” What the heck is that?

Maybe you should re-connect the hose where it’s supposed to be.

This motor only runs for the first minute or two on start up, and at which point it shuts off along with closing the diverting valve. So have you confirmed voltage at motor by back probing the motor leads, and then turning on the truck?

With the air line disconnected from the pump. On start up the diverting valve should open and you should hear a farting sound as exhaust escapes. after a few minutes the diverting valve should close and the farting sound should go away if the valves are working properly.

At least this is how it worked on my old Taurus.

Water can come from a head gasket leak. Do you drive the car regularly. The disconnect on the hose should have been a red flag. IE they did something illegal. You are forbidden by federal law to disable or disconnect emission system components. So why don’t you dump the car? The guy who sold it broke the law and you are the unlucky recipient of a crap car.

What does the secondary air injection (AIR) pump do? Haynes Repair Manual says, “The secondary air injection system is used to reduce tailpipe emissions on INITIAL ENGINE START-UP. …The air injection pump is controlled by the PCM (engine computer) through the AIR relay.” So, once the engine warms up, the AIR pump isn’t used.
Chevrolet has put out a Service Bulletin # 04-06-04-015, dated March 2005, and a revised Service Bulletin #04-06-04-015A, dated December 2006. It states that you must replace the pump inlet tube, and position the tube between the battery and fender. Omitting this, might be the source of the repeats.
If the repairer replaced the air injection pump based solely on the trouble code, that may not have fixed the cause.

You probably have a check valve in the plumbing between the pump and each exhaust manifold. It is there to prevent exhaust gases from going back into the pump.

I would try replacing both of them.

Thanks for all the answers. The factory realized that they screwed up when designing this system. So the work around is to relocate the intake hose up higher and away from the wheel. My guess is that the dealer is the one that did the fix and it should not be illegal because the factory is the one instructing it to be moved.
hellokit the air inlet hose was moved up by the firewall just below the cowl. Do you think that I need to move over by the battery? Where it is place now I cannot imagine that water is getting in there and they put what looks like a factory made breathing apparatus on the end complete with a foam filter on the end of it.
The car is driven regularly (several times a week)and always at least five miles if not more. One clue that may help is the water, and at this time of year ice, reeks of exhaust.
I will try to locate those valves on the exhaust manifold and see if that will do anything. There is what I would call a diverting valve just off the top of the air pump that both sides of the exhaust come into so I may only have one.
Thanks again to all who replied I will let you know more when I get the valve which will probably take a couple of days.

My information, for placement of the hose, comes from the Service Bulletin #04-06-04-015 (and -015A); which says the NEW hose should end between the battery and the coolant bottle. This AIR pump fix applies to Blazers, Jimmys, Sonomas, Bravada with 2.2L and 4.3L engines from 1999 to 2001 (or, 2003).
How urgent is the repair? I gave a hint, when I quoted the repair manual that the AIR pump is active during cold start-up period (until the engine reaches 160F degrees). I would get the pertinent information and do the prescribed troubleshooting BEFORE changing some parts. is a good source for the troubleshooting charts for P0410. And, it’s free if you go to a public library and go to their subscription web site; or, you could buy a subscription.

My third pump failed. I put in the fourth as well as replacing the check valves that come off of the exhaust manifold. They were both bad and were leaking exhaust (which includes water vapor) back into the pump causing the failure. Had I changed these to begin with I would have needed only 1 pump not three. I would suggest to look for your parts on amazon. You can type in the factory part numbers and get them for a lot less on amazon then you can from the dealer. You might be able to get the air pump from a local auto parts store but it will probably be a special order. As far as the check valves go the local guys could not get them. The only other piece of advice I can give is that the check valves did not come off of the lines very easily. I had to unbolt the steel lines from the manifold and then cut through the nut that is attached to the check valve and split it to get if off of the steel line. I did this with a dremel cut off wheel which worked very well. Just be careful to only cut through the nut and not damage the threaded steel line on the inside. Since I completed this final repair of the check valves, air pump, and a solenoid valve all has been well and it has been almost a year now. Thanks for all of the help.
The following part numbers should fit a 2001 GMC Jimmy 4x4 SLT with the 4.3 V6 Air injection pump Dorman 306-010; Air Injection check valve AC Delco 214-638 (You need two); and the Valve Assembly AC Delco 214-1938. Just go to amazon and punch in these numbers and they should come up. Good Luck