linkman

Vehicle is a 2005 lexus gx470 with around 41,000 miles. I had this cel light pop up after some gas attendant in NJ over fill the tank by hammering the pump. I figured it was some gas cap issues and reset it last year and then ran the car some and I passed state inspections. I realized sometime after it was some other problem and figured as long as I can pass its okay. This year however I am having trouble as I can get all but 2 monitors to ok before the cel comes back on. It comes on the following morning or few hours after the car is shut off. I cannot figure out what the code is for exactly. I know it has something to do with the purge control valve. The air monitor of the emission part last year must have been fine in order for me to pass. Does anyone have any idea on how to fix the problem or drive cyle to get the air part ready? p1445 Also how does the evap monitor check run is it setup on some time schedule after car is shut of. Anyway I can bypass that check? I am gettin confused as to what this is. is it the stuck valve or purge issue?
thanks

Ancient

A few months ago, Mann77 posted a diagram of that system and how it works, trouble shooting, etc. I will try and look back for that posting.

I found it, well maybe:

https://www.clublexus.com/forums/gx-...lights-on.html

If anyone knows about the system, he does

linkman

I am confused on the part of which code it could be, is it the secondary air unit or purge control flow? Anyway to make sure before I start taking things apart?

mann777

GX on 2005 models do have this symptom....I suggest instead of your troubleshooting, save the time and have the dealer solved. Use this TSB attached and show it to them, as It may not just be a Gas Cap replacement the fault sometimes continues,Therefore you may need to EVAP System leak test after that clear the DTC. This could be done by the dealer itself.
hope this helps.

GS4_Fiend

iTrader: (22)

P1445 - Air Switching Valve #2 (BANK 2) stuck close: No pressure change (decrease) after the ECM sends an open air switching valve #2 (BANK 2) signal. 2 trip detection logic.

Trouble Area:
-VSV for air injection control circuit bank 2 bad
-vacuum hose for VSV for air injection control, air switching valve #2 disconnected/cracked
-air injector pipe, air switching valve #2 bank 2, (exhaust manifold) cracked
-air switching valve #2 bank 2 bad
-VSV for air injection control bank 2 bad
-Lastly would be bad ECM

Hope that helps.

GS4_Fiend

iTrader: (22)

His problem is not EVAP related. He got an air injection related problem on bank #2.

linkman

I am going to the dealer after I give it a try.. but is it evap related or air injection related?
thanks