I was driving my car and the check engine light turned on. I reset it and after 15 miles it came on again. So I went to Autozone (they check it for free) and the OBD code was P0172. Car is a 98 GS400 60k Miles, with K&N Filter. I just bought the car a week ago.
Their computer readout said "The fuel system for Bank 1 was too Rich. (bank one identifies the location of Cylinder #1, While Bank 2 Identifies the cylinders on the opposite bank."
The guy at autozone said the O2 sensors might be bad. O2 sensor ran $180 each.
I've checked and Chilton does not make a manual. So I went to ebay and bought a Lexus CD service manual. (waiting for it to arrive)
Has anyone else had this problem? I would like to fix it myself because I've done it in all my cars. I had no drop in fuel mileage, and the car accelerates just fine and no hessitation. Idles at 500RPM> Is that normal?
I've done a google search for P0172
Code P0172 can be caused by several problems:
1) Fuel line pressure
2) Injector Blockage
3) O2 sensor malfunction
4) Manifold absolute pressure sensor
5) Engine coolant temp. sensor