P0172 Trouble Code (system too rich bank 1)

**Red97LT1** · 01-06-2007, 01:30 PM

Getting this code for the last couple days. I was told that replacing the 02 sensor before the cat would fix it,but it didn't. The other 02 sensor probably isn't my culprit because it doesn't really monitor the air/fuel mixture. The car idles fine when cold and then it starts to stumble a little when it gets warm.othere than the ses light coming on with this code,the car runs fine. any ideas?

**mrr23** · 01-06-2007, 05:04 PM

maybe a leaking injector on the driver's side?

**BLACKNIGHT03Z06** · 01-07-2007, 05:20 PM

Originally Posted by Red97LT1

Getting this code for the last couple days. I was told that replacing the 02 sensor before the cat would fix it,but it didn't. The other 02 sensor probably isn't my culprit because it doesn't really monitor the air/fuel mixture. The car idles fine when cold and then it starts to stumble a little when it gets warm.othere than the ses light coming on with this code,the car runs fine. any ideas?

I get the same code on my Z06 from time to time. See mods in my sig. It will also stumble occassionally when i nail it at around 4500 to 5500 RPM's. I reset the computer and it will be fine for a while then pop back up.

**Red97LT1** · 01-09-2007, 04:02 PM

My mechanic found out that the MAP sensor was failing and had a vacuum leak. He replaced it and everything is OK now.

**foff667** · 01-10-2007, 08:16 AM

Originally Posted by Red97LT1

My mechanic found out that the MAP sensor was failing and had a vacuum leak. He replaced it and everything is OK now.

cool deal, I was just about to suggest it is probably a vacuum leak...those lean or rich bank codes are almost always a mechanical issue of some sort.