I was needing some helpful information if possible. My truck starts up and runs fine for a few minutes then it will start to run a little rough after a few more minutes it seems like i have a huge cam from the shaking and loping noise. I removed my aftermarket MAF and Programmer and got the engine codes 0174 and 1131 in which I was told was bank 1 lean and O2 sensor switch bad. So I changed the 02 sensor on the passanger side of the truck and I am still getting the same Results. This is a 1997 f150 with a 5.4 liter I do have a cold air intake, poweraide, headers and cat back exhaust. If any one could lend some helpful information it would be greatly appreciated.
Thanks
bdroppedon20s

 

Start looking for vacuum leaks. Follow the PCV valve hose from the passenger's side valve cover to the rear of the throttle body, checking for any cracked or deteriorated connections.

 

this is what i found
P1131 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1

not sure what it means but?

 

Two things:

Vacuum leak - bank two (driver's side). Probably the cause of the poor running.

Did you replace the upstream or downstream sensor? Should have been upstream. Did you reset the PCM and retest after sensor replacement?

Steve

 

im curious how do you reset the pcm? this info could help me thanks!

 

Take the battery loose for a few minutes.

 

I replaced the sensor that is upstream from the cat convertor, I tried spraying all of the vacuum hoses with WD40 which was recommended from another mechanic, i tightened all hose clamps etc that i could find and I did disconnect the battery for approximately an hour and still no luck. any other advice would be appreciated

 

I recently had the same problem with my 2000 5.4L Lariat. There are two vacuum lines on the drivers side. They connect to the chrome tips by cylinder 7 and 8, and then back up to the intake. I had to remove the cover (three screws) to expose the top of the intake manifold. Once I replaced those two lines the truck ran/runs perfect. The one hose was split lengthwise and was not evident. The code reader told me the hoses were bad by the code thrown.