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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

CEL on right bank running lean??

  • Thread starter Thread starter 98blackstallion
  • Start date Start date Jul 25, 2005

98blackstallion

Member
Mar 30, 2005
602
0
17
mtn home arkansas
Jul 25, 2005
#1
  • Jul 25, 2005
  • #1
guys i had my light checked and it showed that the right bank O2 sensor is running lean?? what the hell am I supposed to do about that? I just replaced my NPI intake with a PI one and went 300 miles and then that light comes on. Do i need to replace the o2 sensor? or what do i do? please help guys. thanks
 

jstreet0204

Active Member
Jun 26, 2003
939
0
36
Winston Salem, NC
Jul 25, 2005
#2
  • Jul 25, 2005
  • #2
check for vacuum leaks
 

96WhiteNight

New Member
May 11, 2004
303
0
0
Carlisle, PA
Jul 25, 2005
#3
  • Jul 25, 2005
  • #3
I would replace the O2
 

98blackstallion

Member
Mar 30, 2005
602
0
17
mtn home arkansas
Jul 25, 2005
#4
  • Jul 25, 2005
  • #4
is the o2 bad or is the car running lean?
 

jstreet0204

Active Member
Jun 26, 2003
939
0
36
Winston Salem, NC
Jul 25, 2005
#5
  • Jul 25, 2005
  • #5
The most likely culprit is a vacuum leak causing it to run lean. You just replaced the intake, so you may have a leak around the gasket, to possibly a vacuum hose was left off or came loose.
 

98blackstallion

Member
Mar 30, 2005
602
0
17
mtn home arkansas
Jul 25, 2005
#6
  • Jul 25, 2005
  • #6
well i used adapter plates with my PI intake swap. i didnt figure I would have a vacuum leak there because they seal nicely..is there a way to check o2 to make sure its bad? I dont want to have to a new one if this one isnt bad.
 

98blackstallion

Member
Mar 30, 2005
602
0
17
mtn home arkansas
Jul 26, 2005
#7
  • Jul 26, 2005
  • #7
the right bank is the pass. side of the engine correct? Sometimes i have been in cases were its not. Well I have checked over the motor on both sides and nothing yet. All vacuum lines are intach and in great condition. Intake manifold is torqued down as a spec'd. How do i know which o2 sensor it is on the right side?
 

jstreet0204

Active Member
Jun 26, 2003
939
0
36
Winston Salem, NC
Jul 26, 2005
#8
  • Jul 26, 2005
  • #8
What was the actual code. The code should translate to bank1 or bank2. Bank2 is the drivers side. Anytime I had a bad o2 it gave a different code, like slow response rate. You can check it with a digital volt meter. A Haynes manual will describe the process, BUT if you have a vacuum leak, it will not read within specs, so you could end up buying that you don't need. If you did not find anything visually, you can use a propane torch to find small vacuum leaks. Here are the steps.
  • Fit a piece of tubing to a propane torch Preferably, use several concentric sizes to step the diameter down to about 1/8" I.D.
  • Perform the test with the engine cold so the cooling fan does not come on and disturb the air flow
  • Start the engine
  • Crack the valve on the propane torch to obtain a small flow of propane Direct the propane toward any suspected leaks An increase in RPM indicates a leak.
  • Don't forget to check the intake manifold joints and fuel injector seals
 

96WhiteNight

New Member
May 11, 2004
303
0
0
Carlisle, PA
Jul 26, 2005
#9
  • Jul 26, 2005
  • #9
When i was running lean it through both codes of bank 1 and 2 running lean
 
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