I have a P-0171 erroe code read on my 2001 ford expedtion eddie bauer. It says that it can be in the bank 1 side of the engine of cylinder 1. It says that it can fixed by taking it out and cleaning it. It also says it could also be from not changing oil filter or filter. I haven't done it cuase of my travels in about 8k miles. I need to know if this is a simple problem to fix and how can I fix it.

Facing the front of the truck it is on the left side of the firewall under neath the dryer follow the hoses from the condenser to the fire wall there is a silver dryer cylinder under the wiring harness it is at the bottom of that. Hard to see without flashlight may have to remove the wiring harness from the firewall for easier access

Check for antifreeze leaking on passenger side rear coils.

P0171 - System Too Lean (Bank 1)
This means that an oxygen sensor in bank 1 detected a lean condition (too much oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1.

Note: This DTC is very similar to P0174, and in fact your vehicle may show both codes at the same time.

You will more than likely not notice any drivability problems, although there may be symptoms such as a lack of power, detonation (spark knock), and/or a hesitation/surge on acceleration.

A code P0171 may mean that one or more of the following has happened:
- The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters may cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.
- There could be a vacuum leak downstream of the MAF sensor.

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The P0355 code is, "Ignition Coil E Primary/Secondary Circuit Malfunction" this has to do with the coil(s) and the coil may be going bad, or you have a bad wire / plug (connection) to the coil. P0171 is "System Too Lean (Bank 1)" and P0174 is " System Too Lean (Bank 2)" . The P017X codes mean your ox2 sensors are picking up a lean burn condition. Engine running to warm (hot) or your coolant temp sensor is not reading right or one of the ox2 sensors (Bank 1) is going bad. Hard to trouble shoot this from my computer desk.

You will be told that it is passenger side 02 sensor before the cat,, but it is not .. Drivers side right after the manifold is the one you are after.

Here you have 3 reasons:
1.- Fuel problem: Make sure the fuel is getting to the cylinders at a good pressure
2.- Spark problem: Make sure there is spark at the plugs
3.- Compression problem: Low cylinder compression is a less common cause.

Test it and tell us news.

Take the vehicle to any local auto parts store that will read the codes. WRITE THEM DOWN, and report back here for further help.

on passenger side.close to firewall by the solenoid

bank 1 will be whichever side cylinder 1 of your engine is and bank 2 will be the opposite side. It's named bank 1 and bank 2 so that no matter how the engine is laid out, bank 1 is always on the same side as cylinder 1. I cannot say whether the right hand or the left hand one will be bank 1 as I do not know where your cylinder 1 is. The garage should know

There are four o2 sensors on this truck. one on each side just below the exhaust manifold, and one on each side behind the second catalytic converters. (just about even with the back of the front doors.