I have the P1415 code and I have pulled the check valve from the drivers side AIR system. What are they like when they fail? This one lets air go through from the hose side and seals when a vacuum is applied from the hose side. It seems OK??

I looked at the diagnostic chart but I don't have a scan tool. Since this is only one side, I assume that the pump is OK or it would have the P1416 code as well. Any help on what to check next? Maybe my check valve is bad? What else could it be?

Additional Info: I was waiting for the rig to cool down before I re-started it as I think I read somewhere that this system is only active when the engine is cold.

I started up the Blazer and there is air flowing from the hose the connects to the check valve. There is some exhaust noise and there is some air flow out of the valve. This seems to me to say that the valve is bad. Wouldn't it keep exhaust from coming out if it was doing its job?

 

Exhaust should not be coming out of the hose. If it is, the check valve is bad.

P1415 - AIR System Bank 1
P1416 - AIR System Bank 2

If you only have the code for one side, then the likely cause is that the check valve is bad.

 

The code P1415 is back after replacing the drivers side check valve. After clearing the code, there was no SES light for about 2 weeks. I don't see any issues with the metal pipe or hoses in the AIR system.

One interesting point, the scan tool (at Auto Zone) said that there were two of the 1415 codes stored when I first had the problem. It said that there were two 1415 codes this time as well. Does the fact that it stored the same code twice each time help us narrow things down? Why wouldn't it store the code every single time I start the Blazer?

BTW- 2001 Blazer 4dr. 4X4

 

The PCM can have an stored code and a pending code at the same time. Seems the counter guy at Autozone saw both.

Your problem sounds intermittent... Which is not fun to diagnose.

 

Do O2 problems register right away? Cycling through the warm-up process said number of times before a code is actually registered? Or am I just smoking crack? $5.00

 

I went ahead and cleared the codes with their scanner after installing the check valve. Do they still stay in history after that? I figured that they didn't after having the light come back on and having the same two codes again instead of 3 of the same codes registered.

Can I rule out the AIR pump since it's not both sides showing a code? Could it be as simple as a misfiring plug? O2 Sensor?

 

Do you have any exhaust leaks on the driver side?

 

I don't hear an exhaust leak. I'll listen when under the rig and look for signs of something small. This could be a cause for something like this?


New Info:

If you are standing outside the vehicle, you can hear a small exhaust leak for about 2 minutes after a cold start up. The only thing I can see is some black soot on the bottom of the manifold. It appears to start under the heat shield. I cannot see a crack, just the soot. Are cracked manifolds a common problem? I'd hate to change one..... looks like quite the job.

 

So would a cracked manifold set a P1415? If so, is the R&R of the driver side manifold a big deal? It looks very time consuming....