OBDII ERROR CODE 172 SYSTEM TOO RICH BANK 1 Topic is solved

Guest · Post by **Guest** » 24 Oct 2002, 13:56

HI EVERONE,

ANYONE KNOW WHAT THE CAUSES OF THIS CODE MAY BE?

chriskose · Post by **chriskose** » 24 Oct 2002, 18:20

"TOO RICH" sounds like the fuel/air mixture is off (this is a pure guess, so don't quote me.)

LBourque · Post by **LBourque** » 06 Aug 2005, 13:11

I am chasing PO171 and they both seem to lead to O2 sensors, although I also have a MAF problem. Both are involved with lean and rick mixtures. Good luck!

Post by **dosbricks** » 06 Aug 2005, 19:50

A vacuum leak will cause it to run rich because the ECM is compensating for the extra air in the fuel system. Look at the little rubber vacuum elbows, especially the one hidden on the Pass. side of the intake manifold if your car has one. Engine oil gets in this line from the crankcase vent system and rots that elbow. Left too long, it will kill the front O2 sensor.