2.7 L Secondary Air System Gives Engine Light after Replacement

My Tacoma has had a problem with the Secondary Air System for over a year. Recently I replaced the smog pump and air switch valve and then cleared the codes, I left it alone all day and night, turned it on and check engine light came on. Cleared it again and drove it for a couple of days. Turned it on this morning and check engine light came on! I'm at my whit's end because the codes are P2441 and P2445 and it has all to do with the switch valve which I just replaced. So why the f**k does the godd**n keep coming on with a brand new valve?!

It's this and the evap system refusing to be ready unless a blue moon shows up that keeps me from passing Texas emissions! I want to pull my hair out and bleed to death.

Please give me an explanation.

 

I've heard of those, but the amount, man it costs more than both the valve and pump combined

 

I see what you mean. I definitely agree with how unreliable the system is.

 

I sure hope so, and thanks!

 

Did you replace the vacuum hose, too?

 

Is it the tiny one connected to the valve or the hose connecting the pump to the valve?

 

Little hose goes up to the air intake

 

Well one end of the hose broke off when taking it off the old valve but it had enough slack to connect it to the new valve. I haven't replaced it. I was thinking about doing so but don't know how to remove it.

Am I supposed to replace it too?

 

If only the rubber hose broke then just replace that

 

Alright, if anything I might check both hoses and maybe clean the pump hose if necessary.

Anyone know the inner diameter of the tiny hose?

 

The little hose goes to a pressure sensor not the intake manifold. That is what tells the ECM that it is working or not.

 

What's the inner diameter?

 

I have no idea. Remove the hose and take it with you to the parts store.

 

I might as well do that. Any recommended auto parts store that might carry that type of hose?

 

Any Auto parts store should have a suitable hose for that.

 

Alright

 

So I bought a new hose yesterday. Installed it and then drove around for a few hours only to realize that the same two codes showed up! I'm pissed now. The two codes refer to the valve stuck closed and stuck off from P2441 and P2445 despite replacing it with a brand new valve. Do I need to disconnect the battery now? Because I didn't do that after replacing it. Would it get rid of the codes permanently?

 

Maybe... Give it a try.

There is more that can give those indicators other than the valve actually being stuck closed. The pressure sensor could be defective or the wiring.. or the ECU. Is the pump actually running when commanded?

The below information is from the service manual:

P2441:

Pressure sensor detects no pulsation of exhaust gas despite ECM commanding Air Switching Valve (ASV) to open, while engine running (2 trip detection logic)

Causes:

•ASV (air switching valve)
•Open or short in ASV circuit
•Vacuum hose (ASV - pressure sensor)
•Air injection hose
•Pressure sensor
•Pressure sensor circuit
•Air Injection Control Driver (AID)
•ECM

P2445:

Secondary air pressure less than 2.5 kPa (19 mmHg) despite ECM commanding air pump to turn on (2 trip detection logic)

Causes:

•Air pump
•Open in air pump circuit
•Air injection system piping
•Vacuum hose (pressure sensor - air switching valve)
•Pressure sensor
•Open or short in pressure sensor circuit
•Air Injection Control Driver (AID)
•ECM

 

Maybe some details could assist you in troubleshooting the issue.

Additional information from the service manual:

P2441:

HINT:
Air switching valve normal operation:When the Air Switching Valve (ASV) is open, exhaust gas pulsation occurs in the secondary air passage.
When the ASV is closed, exhaust gas pulsation does not occur in the secondary air passage.

MONITOR DESCRIPTION:

The ECM monitors the pressure in the secondary air passage using the pressure sensor connected to the ASV of the Secondary Air Injection (AIR) system. If either of the following conditions occurs, the ECM interprets it as a malfunction of the secondary AIR system, and illuminates the MIL and sets a DTC:
• Exhaust gas pulsation is detected by the pressure sensor despite the ECM commanding the ASV to close.
• Exhaust gas pulsation is not detected by the pressure sensor despite the ECM commanding the ASV to open.



P2445:

MONITOR DESCRIPTION:

The ECM monitors the pressure in the secondary air passage using the pressure sensor located on the Air Switching Valve (ASV) of the Secondary Air Injection (AIR) system. The sensor measures the pressure in the secondary air passage and transmits a signal to the ECM. If either of the following conditions occurs, the ECM interprets it as a malfunction of the AIR system, and illuminates the MIL and sets a DTC:
• The pressure indicated by the pressure sensor does not reach threshold levels despite the ECM turning on the air pump.
• The pressure indicated by the pressure sensor exceeds threshold levels despite the ECM turning off the air pump.

 

Would the ECU fuse be a problem too? The fuse hasn't blown yet but what if I replace the fuse anyways?