2006 lx470 CEL, VSC Trac, VSC OFF, manifold leak P2197 (1 Viewer)

[kernelmax]

Hi everyone, I have a lx470 bought a few months ago. It had the CEL, VSC Trac, VSC Off lights on and I ran the OBD. It said the O2 sensor (bank 2 sensor 1) was off so I replaced all 4 O2 sensors. But just a few days after the replacement, I got the CEL back on dash again and same error code. I've tried to erase the error code several times with OBD and sometimes it 1 day later or sometimes a week or so. I found that the CEL lights usually came on when I merge onto the freeway with a higher speed or when I floored it after I erased it. The codes are following:

P0171: System too lean (bank 1)
P0174: System too lean (bank 2)
P2197: Oxygen (air/fuel) sensor signal stuck lean (bank 2 sensor 1)

Also, I did found that my lx470 has a exhaust manifold leak (on the driver side I believe). The leak sound is pretty obvious when the car is cold and windows down but not so obvious when the car is hot and windows up. Is it possible that those O2 sensor error code is because of the manifold exhaust leak since it's bank 2 sensor 1, the O2 sensor before the cat? Due to the leak in manifold, more/less air is pulling into the exhaust thus giving a incorrect O2 sensor reading. Could there be any other possible reasons that throw those error codes?

For the new O2 sensors I used, I bought them from some ebay cheap brand. Should I try Denso instead?

Any advice will be appreciated! Thanks in advance!

 

[WonkieWheel]

What strange timing. In doing a google search earlier today, it stated that an exhaust leak can cause an oxygen sensor error. Coincidently, my 07 LC also lit my dash with CEL, VSC Trac and VSC Off lights last night. However, my OBD II error codes are P0138 (sensor 2, bank 1 - high voltage) and P2195 (sensor 1, bank 1 - signal stuck lean). After I learned that an exhaust leak can cause the O2 sensor error codes, I immediately contacted an exhaust specialist since I know I have a bad muffler. My guess is my LC also has an exhaust leak in addition to a bad muffler. Did you look at your freeze frame to gather details on the error codes? In addition to an exhaust leak, a faulty MAF and lost pressure due to a leak from your manifold or hoses can also cause O2 sensor error codes. I will circle back in a week or two after I am able to meet with my mechanic (booked for about 10 days).

 

[kernelmax]

What strange timing. In doing a google search earlier today, it stated that an exhaust leak can cause an oxygen sensor error. Coincidently, my 07 LC also lit my dash with CEL, VSC Trac and VSC Off lights last night. However, my OBD II error codes are P0138 (sensor 2, bank 1 - high voltage) and P2195 (sensor 1, bank 1 - signal stuck lean). After I learned that an exhaust leak can cause the O2 sensor error codes, I immediately contacted an exhaust specialist since I know I have a bad muffler. My guess is my LC also has an exhaust leak in addition to a bad muffler. Did you look at your freeze frame to gather details on the error codes? In addition to an exhaust leak, a faulty MAF and lost pressure due to a leak from your manifold or hoses can also cause O2 sensor error codes. I will circle back in a week or two after I am able to meet with my mechanic (booked for about 10 days).

bad news... A friend of mine was driving it and was hit by a car running through a red light. Probably totaled... but hope you find the cause of the error codes on yours!

 

[2001LC]

06-07 have a known bad fuel pump in 5 out of 10. Which replacing fuel pump and fuel filter corrects.
It's typical symptom, is in summer when hot. We accelerate to ascend a mtn. pass, pass traffic, enter HWY, etc. This put fuel pump into high speed mod. Which it then runs hotter. Heat of day and heat from pump running faster and heat in wires from pulling more volts/AMP. Increase electrical resistance. As we let off gas pedal, fuel pump drops to lower speed. Fuel pressure/flow drops too much, due to higher resistance lowering AMPs to pump. We see, BK1 & BK2 lean condition, engine stalls.

Don't assume tick-tick-tick an exhaust leak. Make sure!

Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert!

TICK TICK TICK POP POP POP is a ticking time bomb, often mistaken as exhaust manifold crack or gasket leak leak. ALERT, ALERT, ALERT: Spark plugs are working themselves loose. "Walking Out" Then blowing out of head, taking their female threads of head with them! Very damaging! You think TICK...

forum.ih8mud.com

 

[2001LC]

Since you've the VVti
Do the filter mod:

S.A.I. Filter Modification, in VVT engines. To prevent its failure! Alert Alert!

We've a $2.00 part in the S.A.I. (secondary air injection) system of the VVT engine, that is taking-out ~$7,000.00 $15,000 $25,000 (inflation) in parts. WOW! I've a very easy and cheap WORK AROUND. You are going to love this ;) This thread is dedicated to the 4.7L 2UZ-fe VVT engine, in the...

forum.ih8mud.com

 

[WonkieWheel]

bad news... A friend of mine was driving it and was hit by a car running through a red light. Probably totaled... but hope you find the cause of the error codes on yours!

Wow! I hope your friend is okay! I love my LC, so I hope to learn more once I get a new muffler/exhaust system.

 

[WonkieWheel]

06-07 have a known bad fuel pump in 5 out of 10. Which replacing fuel pump and fuel filter corrects.
It's typical symptom, is in summer when hot. We accelerate to ascend a mtn. pass, pass traffic, enter HWY, etc. This put fuel pump into high speed mod. Which it then runs hotter. Heat of day and heat from pump running faster and heat in wires from pulling more volts/AMP. Increase electrical resistance. As we let off gas pedal, fuel pump drops to lower speed. Fuel pressure/flow drops too much, due to higher resistance lowering AMPs to pump. We see, BK1 & BK2 lean condition, engine stalls.

Don't assume tick-tick-tick an exhaust leak. Make sure!

Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert!

TICK TICK TICK POP POP POP is a ticking time bomb, often mistaken as exhaust manifold crack or gasket leak leak. ALERT, ALERT, ALERT: Spark plugs are working themselves loose. "Walking Out" Then blowing out of head, taking their female threads of head with them! Very damaging! You think TICK...

forum.ih8mud.com

I will definitely look into the fuel pump/fuel filter as I investigate the error codes. Thanks!