Wife's 2013 Equinox 2.4 has had a recurring P0411 secondary air injection low flow code for about a year. Googling turns up that this is yet another delightful feature of the Ecotec 2.4, with a variety of causes. So far I've determined the electric air pump runs, because I can hear it. The condensation and ice that are known to build up in the air hoses does not seem to be the case, and the hoses aren't clogged. The check valve and carbon build up in the ports seem to be the last two possibilities, but is there an easy way to test the valve?
2013 Chevy Equinox P0411
- Thread starter Dave Sherman
- Start date
- Status
what are the prices for parts on rockauto?
edit: looks like the check valve is 138 and the air pump 114.
Maybe someone can link a service manual or procedure for troubleshooting those.
have you had any issues with the vvt solenoids? every 2.4 thats been in the family has had them crap out.. sometimes as low as 50k miles.
edit: looks like the check valve is 138 and the air pump 114.
Maybe someone can link a service manual or procedure for troubleshooting those.
have you had any issues with the vvt solenoids? every 2.4 thats been in the family has had them crap out.. sometimes as low as 50k miles.
Do you have a scan tool with Bi-Directional Control functions?, Each check valve has a pressure sensor built in & need to be checked for operation with the air pump running (Check Valves open & closed).
Yep, both of hers died within a month of each other at around 40K. At least the replacements were relatively cheap and they are holding up.
I did pick up a bidirectional scan tool, thanks to Amazon Prime. Xtool Anyscan A30D. Here's what I've learned so far:
-Pump turns on when commanded.
-Both check valves are clicking
-With the pump off, valves closed, engine off, both pressure sensors are reading 14.2 PSI (atmospheric).
-With the pump and valves on, engine not running, pressures sensors are reading about 16 PSI. Don't know if that's normal or not. I wonder if it's higher than expected and it's pointing to clogged air injection ports.
-P0411 is the only DTC being set.
Only thing I'm puzzled on is the tool has two sets of readings; one has "pressure sensors" bank 1 and 2, and both are showing the 14.2 or 16. The other group says "pressure reading" bank 1 and 2, but those are showing zero.
I cleared the DTC to see if it comes back. I'm hoping that if it can stay off long enough to get through the e-check station, it turns out the test result is good for a year, so maybe if can cross my fingers and get it to pass, we have about 2 1/2 years to save up some pennies to hopefully get something else.
If it is the clogged ports, is it in any way possible to spray some solvent into the injection ports, like that stuff for cleaning direct injection intake deposits? Cleaning them up "by the book" involves taking the cat converter and exhaust manifold off, and replacing the exhaust manifold studs and gasket. Not sure if I'm up to attempting that.
-Pump turns on when commanded.
-Both check valves are clicking
-With the pump off, valves closed, engine off, both pressure sensors are reading 14.2 PSI (atmospheric).
-With the pump and valves on, engine not running, pressures sensors are reading about 16 PSI. Don't know if that's normal or not. I wonder if it's higher than expected and it's pointing to clogged air injection ports.
-P0411 is the only DTC being set.
Only thing I'm puzzled on is the tool has two sets of readings; one has "pressure sensors" bank 1 and 2, and both are showing the 14.2 or 16. The other group says "pressure reading" bank 1 and 2, but those are showing zero.
I cleared the DTC to see if it comes back. I'm hoping that if it can stay off long enough to get through the e-check station, it turns out the test result is good for a year, so maybe if can cross my fingers and get it to pass, we have about 2 1/2 years to save up some pennies to hopefully get something else.
If it is the clogged ports, is it in any way possible to spray some solvent into the injection ports, like that stuff for cleaning direct injection intake deposits? Cleaning them up "by the book" involves taking the cat converter and exhaust manifold off, and replacing the exhaust manifold studs and gasket. Not sure if I'm up to attempting that.
According to the GM service information, the Secondary AIR system will set code P0411 when both the AIR pump and AIR solenoid are commanded ON but the system pressure falls outside the expected 0.7-1.9 PSI above the BARO reading. Your reading of 16 PSI while operating falls just within range (1.8 PSI). My bet is clogged ports, and I doubt you'll have much luck with carb clean. Manifold removal is in your future.
Yuck. Well, looking at a Youtube of it, removing the exhaust manifold doesn't seem quite as daunting as I thought. Probably not much worse than removing the intake manifold to clear the PCV port, which I have done, and probably less of an undertaking than the Pilot's timing belt. Just have to hope the rusty studs don't shear off. The CEL came back on already, though curiously it did not come on first thing in the morning as I would have expected, wife says it came on when she left work. I think you're right, it's on the hairy edge of being just out of range. Gotta love that GM's TSB for the clogging AIR ports mentions that there is no permanent fix.
Have the computer flashed with a non-AIR calibration? Kidding, good luck with the repair!
Ugh, think I'm going to have to admit defeat on this one. Finally got around to attempting to remove the exhaust manifold. Not going to happen. It's very tight in there, and the air injection lines are in the way. I got one of the check valves off, and since I had one new one, took apart the old one. It was caked with soot. I tried running some lacquer thinner through its mate, and it did give up lots of black stuff. On the other hand, with one new check valve and one slightly clean, the back pressure did come down slightly. Not enough to get rid of the P0411, but it did go through a a few cycles before it came back. Got another new check valve on the way.
Thinking it may be time to pay the man. Even in the Youtubes I've watched they say it's a tough job. If two new check valves can't improve it enough to get it pass e-check, then maybe its time to let a pro handle it.
Thinking it may be time to pay the man. Even in the Youtubes I've watched they say it's a tough job. If two new check valves can't improve it enough to get it pass e-check, then maybe its time to let a pro handle it.
Trying one last "hail mary" before I take it to the shop. Replaced the other check valve, pressure was still up around 1.9 PSI, right where it triggers a P0411. Tried pulling the hose off the air box for the air pump, shot some carb cleaner in, and commanded the pump on with the scan tool. Got a whiff of some carb cleaner at the exhaust. Turned it all off, let it sit for a while. Started up the engine, commanded the secondary air injection on, and now it's down to 1.8 PSI! Maybe that helped clear some of the soot. Don't know if some GDI intake cleaner would do a better job, but we'll see if the light stays off for a little while.
- Status
Similar threads
