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P1151 - Bank 2 Lean

  • Thread starter Thread starter Tripoli
  • Start date Start date Mar 13, 2008

Tripoli

Member
Mar 30, 2005
208
0
16
Dallas, TX
Mar 13, 2008
#1
  • Mar 13, 2008
  • #1
I've been having my fair share of codes lately from a short I experienced recently. I believe I finally have all that worked out, but after 4 days of no SES light, this code popped up again this evening. My fix 4 days ago was to re-seal (as best as I could) the 2 slip joints on my LT headers on the driver's side. Before that, I was getting both this code and P1150 - Heated Oxygen Sensor Switch - Adaptive Fuel Limit - Bank No. 2. (Can someone confirm that bank 2 is the driver's side?)

There are no recent mods to the car. The only tinkering I've done is messing with the idle (both in the tune and the throttle stop screw) and fixing my short, which included everything on Fuse #8, which included this O2 sensor. I have set the idle back to where it was originally in my tune (800 RPM), but the throttle stop screw is still set with the throttle relatively open.

Could I possibly have re-wired the circuit so that the sensor is getting less voltage, causing the lean reading? Do y'all think that my 109,000-mile-old oxygen sensor might have kicked the bucket, possibly because of the afore mentioned short?

I really want to take care of this before putting my new heads on, so y'all's help is greatly appreciated.
 

Green&GoldGT

Member
Aug 1, 2005
302
0
17
Virginia
Mar 13, 2008
#2
  • Mar 13, 2008
  • #2
I believe this was the same code I got a few days after I got my LTs installed. I heard that a lean code is thrown when its over 20% lean. Since I've added fuel through my XCAL2 and I've never thrown the code again, but I do have a hesitation between gears that comes and goes.

Do you have an aftermarket MAF?
 

Tripoli

Member
Mar 30, 2005
208
0
16
Dallas, TX
Mar 13, 2008
#3
  • Mar 13, 2008
  • #3
Green&GoldGT said:
I believe this was the same code I got a few days after I got my LTs installed. I heard that a lean code is thrown when its over 20% lean. Since I've added fuel through my XCAL2 and I've never thrown the code again, but I do have a hesitation between gears that comes and goes.

Do you have an aftermarket MAF?
Click to expand...
No, my MAF is stock.

It's odd because I didn't have this problem for the past year, ever since I got cams and a tune, but it just showed its ugly face after my electrical issues.
 

screamin gt

5 Year Member
Apr 9, 2007
393
6
28
central CT
Mar 13, 2008
#4
  • Mar 13, 2008
  • #4
bank 2 is driver side. I had a p1131 and p1151 if I remember right, and one was a drivers side header to h-pipe leak and the other was passenger o2 sensor.

I could be wrong cause that was last fall so its hard to remember. I know I also had a third code which was the mass air meter needing to be cleaned, but I don't remember that code #.
 

Tripoli

Member
Mar 30, 2005
208
0
16
Dallas, TX
Mar 13, 2008
#5
  • Mar 13, 2008
  • #5
Ah! Some good news tonight. P0155 (Bank 2 O2 circuit manfunction) came on tonight along with P1151. I suspect the "low" voltage reading is, in fact, zero volts due to the circuit fault. A bit annoying that P0155 didn't come on for 5 days, but better late than never. I suspect I can fix this.
 
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