2009 Chevy Malibu 3.5L Code P0411
Good evening everyone
Today I have a 2009 Chevy Malibu 3.5L V6 with 277,210 miles with code P0411.
In the past two years ago, the engine was replaced because the driver had overheated the Motor. It also had a problem with the code P0411 when the engine was replaced because the wrong engine was installed since it did not have the Secondary Air Injection Ports on the head where the Exhaust Manifolds are.
Anyway now in this case it is something different. Both Secondary Air Injection Solenoids were replaced with some spares lying around the shop, and it has returned with the same issue.
I then received the vehicle preceded with a code scan, and of course as already stated above the code P0411 was there.
Next I ran an Air System test on the Scan tool for the Secondary Air Injection system.
Upon test, the Secondary Air Injection Pump, and solenoids would work, and turn on. I don’t know what got to my head to do it, but glad it did but I prompted to unplug one Air Injection Solenoid, and then proceed to unplug the next, and I can only get an audible click from the Solenoid on the Bank 1 side Air Injection Solenoids, and not the Bank 2 side.
This the Bank 1 side
And this is the Bank 2 side
Pulled out the Wiring Diagram for the Secondary Air Injection Solenoid
*Note from Freeze frame fault data I had a suspicion that there was some kind of wiring issue because the data had indicated that the fault took place when the Air Injection System was not commanded on, so I thought that was bit odd.
Anyway I proceeded to Check Voltage to Secondary Air Injection Solenoid, Ground, and 5V Ref. all were there but the Ground. No ground when I applied an incandescent test light to power to the ground pin and the test light did not light up, Aha!
With the Black Ground wire pierced and with 12V being applied through the test light I tugged some wiring around the vicinity of the Air Solenoid, and the test light would flicker on, and off as I tugged on the harness. I was able to narrow it down to the Ground on top of the transmission casing.
Went on to repair the ground, and routed some of the ground connections back to the top of the transmission casing, and some of the other to the grounds Left of the chassis as pictured so I just wouldn’t over clutter the same area with terminals.
what is the red Matco tool you are using there for soldering? Looks interesting!!
Glad you asked, its a Soldering tool from Matco its made out of aluminum billet, and each end has a clamp so as you solder the wire it can hold both ends of the wire together. The black nob is so you can turn it to feed some solder as you heat the wires with the soldering iron with your other hand. Inside the handle there is a spool of soldering iron where you can refill it. I mainly just use it to hold both wires together as I solder.
Thank you! I have found it on their site;
I'll have to check with my Matco man to see if he has one.
Thanks for sharing, good case study and diagnosis!
I just got into this group today, and also just figured out a stubborn p0411 on 2008 Cobalt, CAL emissions vehicle. Following the flow chart to a "T" this particular vehicle passes all flow chart test and leads to "all ok" system test and verify dtc does not set.
This vehicle already had a new from dealer secondary air valve, a new PCM , MAP, when I took a peak. I did the testing exactly as flow chart stated and specs were just in spec for pressure readings steps 18 and 21, I figured flow must be a bit down, tech working on vehicle voltage dropped pump and was good, so we took a stab at a secondary AIR pump... of course same results, will pass the flow chart required pressure rises but fails on cold start UGH!! (i dont know if we can mention Identifix in here LMK if I am breaking the rules) IDFIX test procedure 475551 , the pressure rise ( dead head the pump) KOEO was 3.4 volts,, and pump and solenoid on pressure was 3.1 volts , they called for 2.9 so we were looking for a restriction in the system when the gasket between the solenoid valve and head was found blocking off aprox 1/3 of the passage. Properly reinstalled gasket and vehicle passes.. .2 Volts was the difference here!! I missed great opportunity for photos and screen shots but here is dead head test...
Nice! Amazing work Mann. Ran into a similar problem as well with this same vehicle about two years ago when the engine was replaced. It was setting the P0411 code, and what ended up being the problem was since this vehicle was a California vehicle emissions application the engine installed was a just a federal emissions complaint assembly so the exhaust ports for the secondary air injection system were not accommodated for the vehicle with that emissions application. So another engine with the California emissions application for the engine assembly to accommodated those exhaust secondary air injection ports had to ordered, and installed. Luckily the engine was still under warranty.