What is Bank 1?
matt79
08-18-2007, 08:29 AM
I scanned the check engine light. I got code PO 420. Which says catalyst efficiency below threshhold (bank one). So where is bank one located? I'm guessing it is the O2 sensor on the rear exaust manifold...
GTP Dad
08-18-2007, 10:11 AM
Welcome to AF!!
Most of the single exhaust cars only have bank one. Some do have two banks but in your case I suspect you either have a cat issue or the O2 sensor is bad. The sensor is easier to change but if the code does not go away you will need to change the cat.
Most of the single exhaust cars only have bank one. Some do have two banks but in your case I suspect you either have a cat issue or the O2 sensor is bad. The sensor is easier to change but if the code does not go away you will need to change the cat.
MasterTech8
08-18-2007, 10:49 PM
On a V6 or V8 engine bank one is the side of the engine that cylinder one is on. Then bank two is the side of the engine that cylinder two is on
xeroinfinity
08-19-2007, 10:49 AM
Actually if it is a V8, bank 2 is on the right (passenger side).
Sensor 1 is always before the catalytic converter (sensor 2 is after)
Sensor 1 is always before the catalytic converter (sensor 2 is after)
Ron G.
08-19-2007, 01:14 PM
In the 3.1 engine (transverse mount) bank one is at the aft (firewall) side.
In the 3.0 & 3.3 engines (transverse mount) bank one is at the fwd (radiator) side.
In the 3.0 & 3.3 engines (transverse mount) bank one is at the fwd (radiator) side.
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