TOLex168

Hello,
Could anyone help with part number or name? Refer to attach diagram, I need the gasket around the link (the gasket around the mechanical part that move in/out and up/down). Saw/read somewhere the guy replaced this part solve the P0171 after he changed everything would not help.

Background: Get P0171 system too lean bank 1 sensor. Get this code only when idle for a while. Reset the code and drive a few weeks without codes.
Lexus ES330, 2005 at 187K miles
Get only 250 miles per fill up almost a year now. But get around 350-375 miles on freeway.
Reset ECU, clean every thing, but would not help.
In Winter (when it cold below zero (-4F/-20C), no power when step on gas and rev to 3K rpm even after 5min of warm up.
Changed coolant sensor in Spring, not help with no power when cold

SUSPECT AIR LEAK SOME WHERE -- clean everything (MAF, and others) and check all the host but would not help.

Any advise would be great. Next would be O2 sensor.

nsghtbrwry

That would be the ACIS gasket. Dealer only. Very rare for that metal crush gasket to fail, most people don't even know it exists.

I'd grab a can of propane or carb cleaner and see if you can get the idle to change by spraying around hoses. Also, clean the battery terminals - these cars throw red herrings when the electrical system is not up to par. Past that, O2 sensor is the least likely, with a properly-functioning electrical system and Denso sensors, faults with those are pretty cut-and-dried. Check your fuel trims with a scanner.

TOLex168

Thanks you for the info. I have not clean that gasket, just look around. I did check all the plastic hosts for leak and clean the in take air system once a year as routine maintenance. Battery just replaced in early Spring and clean the battery pole/connector once a year. The car could run for months without throwing the code in city 250 miles per fill up (used to get 290-320), it does better on freeway. Just throw the code again last Friday while waiting at McDonald's drive through.