i have a 97 f150 scab with a 4.6l and i been havin trouble with the p0401 and p0156. i changed the egr and egr solinoid, cleaned the throttle boby and the intake manifold, put new plugs and wires new fuel filter. and replaced the o2 sensor on bank 2 sensor 2. now i have more codes pop up. ill start at the p1157,p1408,p1464,p1703 and the p1780. are these hard to fix or is there some golden screw driver i need to fix this? it shows to have 232000+- im not sure how many miles after that cause the odometer stopped there. the motor was replaced but i dont know when or how many miles it had on it. please any and all advice is needed. if all y'll can suggest is a bullet i can do that too. thank you in advance.

 

You start at the lowest code number as it's problem can create the higher code numbers. After you fix the codes lowest number clear all memory to prove out you fixed your 1st code and see if any others appear. Then carry on with the next lowest numbered code if any appear.

 

i changed the o2 sensor but im getting different stories as to where the bank 2 sensor 2 is i changed the 1 in the passenger side is that right?

 

No
Bank 1 is the side with cylinder#1
Bank 2 is drivers side
Sensor 2 is post cat

ps p0156 is a circuit malfunction,it's possible that there is a wiring harness /connector problem or the sensor it'self.
Check the harness around the exhaust for melted wires.

 

ok great thanks. ill go out and switch sides on the o2 sensor and see if i still get the same code. i hope i wont.

 

Swapping senors won't fix anything.
The code 156 and 1157 are for the same fault with sensor 2 on the driver side. Wire, corrosion,crosses etc.
If you list the codes then look them up to see what's common, you will see two main issues.
One is the 401 low flow code, the rest are all over the place and does suggest a harrness issue.
On an unknown truck with high mileage you need to inspect everything for issues.
The 401 code is a low flow test failure of the EGR system.
It could be the DPFE, the vacuum regulator that operates the EGR or the ports behind the EGR are plugged with carbon.
Might as well get used to not hoping for anything and go at it to clear the problems until you get them all.
Things are way more complex than you are realizing.
Each time you repair something, clear the codes and see what comes back so you don't keep chaseing old history.
Good luck.

 

Listen to Bluegrass I just went through the same thing on my 99 4.2 the hole problem was the wire harness to the transmission, I change that out 22bucks junk yard and all is well good luck most of the time the wires melt right around where the come up @ the back of the motor

 

Think he was swapping the sensors to see if the fault migrates with it or stays with the harness.

 

yes i was talking about swappin from pass to driver and see if the code goes from 1 to the other.and how does the harness from the tranny have anything to do with the egr codes?
i cleaned all the carbon fron the intake, throttle body and the tude that goes from the back of the egr.

 

Read again.
The EGR is a seperate fault. I gave several possbilities for the cause.
The 401 code is telling you there is low flow on a test for the system.
It is detected by the DPFE sensor and reported to the computer for comparison with a table of expected values.
When the reported value is outside limits, the code is set.

 

ok i changed and cleaned everything but the dpfe that comes next.should i get it from the dealership or is autozone or napa ok?

 

Dealer only.
The tests done by the system are to tight in tolerence for after market part reliability.

 

ok well its off to the dealership i go. thanks everybody

 

any luck at the stealer ship ?