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DTC P0410 Sec Air Injection - How to Repair and Part#s

05-13-2006, 06:02 AM
99-01 Blazers with the 4.3L motor and 00-03 2.2L motors have the Secondary Air Injection system and I've listed the codes, part #s, circuit description, and have to fix below.

DTC P0410 (SES Light On) - Secondary Air Injection
P1415 and/or P1416 for secondary air injection Bank A and B can also be set if the powertrain control module (PCM) detects a heated oxygen sensor voltage mismatch and activates an internal test to confirm.

Circuit Description:
This is located under the radiator (pump, electric solenoid, and vacuum shutoff valve) and tees off up to the exhaust manifolds thru 2 check valves on 4.3L. For 4wd remove the front skid plate to access. The secondary air injection pump is used to lower tail pipe emissions on start-up. The PCM supplies a ground to the pump relay, which energizes the pump and the electric solenoid valve. Engine vacuum is applied to the shut-off valve when the solenoid is energized. The engine vacuum opens the shut-off valve that allows air to flow to the exhaust manifolds. Often the pump gets water/moisture in it and freezes up blowing the fuse and the check valves rust or freeze open internally and then burn thru the rubber hose, and even melt the lower “T”, shutoff, and even pump impeller.

Check/Replace as required:
1. You should hear the pump on starting the Blazer and if you put your hand on it you will feel it running for about 1 minute. Part #12560095 (AC Delco 215-364) Pump, Sec Air Inj for 1999-2000 L35 (4.3L) or #12568324 (AC Delco 215-425) Pump, Sec Air Inj for 2001 L35 (4.3L) + 2000-2003 L43/LN2 (2.2L).
The GM # is on your current pump so check it because the Dealer is very confused and/or out of these and will sub other pumps. You can remove the pump and take the #25 torx screws out and see if the impeller is clogged, rusted, melted, etc before spending $100-200 for it. Impeller should spin freely.

2. Extend the air intake hose that ends halfway up the passenger side of the radiator about 2 more feet so it can run between the battery and coolant reservoir and push into the fender hole to keep dry. 99-00 is 5/8 heater hose and inline connector and 01-03 is 3/4 heater hose and inline connector –check size.

3. #12558992 (AC Delco 215-638) air injection check valves 2 required – most stores sell these for $12-20 each or Dealer $33 each. If they rattle or the hoses are burned thru replace – should only flow air into the exhaust. The easiest way is to remove the two 13mm nuts that mount the check valve pipe to the exhaust manifold and use a vise to hold them – trust me here. The little exhaust gaskets should be reusable.

4. #10217106 connect (hoses) 2 required check valves to pipes (Dealer Only $7 each). If burned thru or hard/brittle replace. Usually a good thing to plan on buying!

5. #12555165 secondary injection shutoff valve (vacuum operated in the ¾” hose in the pump outlet to the “T” pipe under the Blazer (Dealer Only $27). Only open when the pump is on and vac applied. Also replace the 5/32” vac hose from the solenoid to valve and solenoid to intake (about 4 ft of it). Once you extend the air intake listen to the hose end and you should not hear any exhaust noise after the short initial one minute pump run – if you still do the vac diaphragm is stuck open/clogged/burned so replace. Vac is applied by an electric solenoid mounted by the pump #01997264. The center vac port goes to the intake manifold vac and the off center vac goes to the shutoff valve above. The vac should only be applied to the shutoff valve for that 1 minute as the Blazer starts then is switched off. Hose clamps will be needed here.

6. #10105352 “T” for under Blazer where pump outlet to both pipes connect – if yours melted! One end is ¾” and two are 5/8”ends - but you can use a ¾” on all ends with a little lube. Hose clamps here too.

7. The pumps 30 amps Maxi-fuse (large size) is under a little black cover between your battery tray and inside the passenger side fender. You may have to remove your battery to get to it. Depress the little cover retainer and remove, then pull the large fuse out to check/replace. There’s also a 10 amp small fuse to check for the electric solenoid that controls the secondary injection shutoff valve mounted by the air pump.

8. If you need the 2 lower hoses that connect the metal pipes to the “T” going to the pump here’s the bad news – Dealer Only and includes the pipes so over $100.

That’s all there is to it – Enjoy.

05-16-2006, 04:21 PM
Thank You!

01-22-2007, 03:37 PM
Thank You!!!!!

07-12-2007, 03:03 PM
wow... i havent posted here in a while and i just wanted to point out that

1) i like the new(ish) way things are organized and
2) i LOVE the fact that AF might be the best website EVER.

kudos on the info, btw.

11-20-2008, 12:54 PM
Got the P0410 code. Went through all the postings and came across one from an Oldsmobile person. Something I had not thought of. I was looking at all the sensors and gas cap. The ultimate fix was replacing the spark plugs. I had not done that in a while (about 50k miles). After replacing the spark plugs I started the car and the "Check Engine Soon" light was still on. I drove a couple of miles and had to fillup the gas. Started the car again and the "Check Engine Soon" light went off and has been off. Forgot, that sometimes it is the basics that need to be performed before looking at the sensors. Also, you will need a special wrench to get to a one plug, the one on the drivers side, because of the steering column. Thanks for all the postings.

07-11-2010, 07:05 AM
I am working on fixing this on my Jimmy.

Does anyone know what this part is called or the part number? it is from a 2001 GMC jimmy 4x4 I need to replace it as the small vacuum niple broke off. (
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07-11-2010, 11:00 AM

07-11-2010, 12:52 PM
Thanks, I know what the airpump is, & this is not it. This part has a small vacuum line fitting(Which I broke) & 2 big vacuum fittings and is located next to the air pump

07-11-2010, 12:58 PM
Here is a pictures of the assembly when I had it off my truck, the part in question is on the right of the pump... (
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10-28-2010, 07:17 AM
Is that the solenoid your looking at ? Can you put an arrow on your photo to point at the part ? That looks like the Air chamber that belongs on the pump ..;-)

10-28-2010, 07:23 AM
HI Bob,

Thanks for getting back to me on this, I forgot to post that I am all set, I ended up getting another complete setup off a parts truck my buddy had, so I'm all set :)

10-28-2010, 10:06 AM
That is one rusty piece of metal

11-02-2010, 12:09 PM
What you need is: #12555165 secondary injection shutoff valve as stated in the first post.

Jimmy Ford II
08-25-2013, 02:47 PM
Well it looks like I'm in the same boat now too. My 99 Jimmy SLT has been throwing a cpl different emission codes since I picked up a scan tool trying to nail this b* down. I've had an evap code and now P0410 secondary air. I've recently dropped my fuel tank to replace fuel lines and took a look through the evap hoses up in there and around the charcoal canister for any loose, dry rotting and cracks. None found. Further, I've reset the MIL and monitored all the tests completion status. I did notice that while all other tests completed (without any MIL) the secondary air test took a solid month+ to complete (and ultimately fail throwing the 410 code immediately). And I even did what I could to enable to ideal condition for that test to complete. So that seemed a conspicuous clue which no surprise now led to the 410 code which brought me here to muddogs very helpful post. First question, does the vehicle have to be 'cold' before starting for the air pump to run on start up? Second, I think theres a part # typo in muddogs point #3. After researching his details I believe he meant part # AC Delco 214-638.

Anywho, I've looked over my air2 system and I don't find any evidence of melting damage or loose, dry rot, cracked hoses, etc. anywhere in the system. The check valves are pretty firmly mounted to the pipes so I can't really shake check them for rattle. Although the little bit of handling them I tried, I found no rattle. And, the passenger side fuse bus (which I almost completely missed) fuses (30A & 10A) check out fine. When I started her up this afternoon I did not hear nor feel the air pump running or find any suction (or pressure) at the intake end of the hose tested by my finger over the hole method. So, I'm wonder, since this is for improved emissions at start up, that this is meant for a cold engine start. Next, I intend to wait overnight or at least 8 hours and see if I can confirm the air pump on at start up. subsequent to that verify power and ground to the circuit. Incidentally, I see the wire connector to the solenoid, but whats that larger box with electrical connector mounted forward and above the solenoid? Any further trouble shooting suggestions would naturally be greatly appreciated.

12-02-2015, 11:04 AM
I know this thread is old, but I recently blew my 1993 4.3 and had a used 4.3L from a 1992 installed. The new/used motor does not have the air injection, but the mechanic use my old exhaust manifold and basically tried to braze over the fitting/hole on the exhaust manifold.

My question: Do I need to do anything to the motor? Does it need to be reprogrammed or anything?

Sometimes the truck seems to run great, other days it feels sluggish.

P.S. I always hear an exhaust leak somewhere, which could be coming from the brass braze on the manifold (it looks like it might have a tiny hole in it).


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