An otherwise pretty solid truck, made it's way up to Fort Drum, NY from Texas so I'm trying to knock out as much as I can before the corrosion, errr snow, starts.

The biggest concern at the moment is a rough idle. The seller told me they thought it was the MAF, but I have since determined it is not. Codes say the 1 and 2 O2 senors, so I picked those up and will be swapping them out. Also disconnected spark plugs to test them while running and there was no significant change, so may I need a new set of them too? The odometer says 210k, but the seller told me he put in a new engine and xmsn around 120k ago. No way to know for sure, but at this point people at the local Auto Zone are just kinda throwing darts at potential problems.

Any other ideas/tips for things to replace for a pre-winter tune-up on an essentially unknown F150 of this type? Rather than invest too much in an undercarriage liner, I may try out Rust Check http://www.rustcheck.com/ Does anyone have any experience with it?

I've got a new set of headlights on order for a cleaner and more modern look, I replaced the rear shocks today, and look foward to having a project truck that I will (hopefully) spend more time driving than fixing.

Thanks in advance, glad to be a part of the community!

 

What are the specific codes? Most of the time an 02 sensor code is thrown, it's not the sensor but something else causing the fuel mixture to be off such as a vacuum leak. Definitely change the plugs if you don't know how long they have been in the truck plus change all the fluids and filters, pcv, etc. Torque the plugs to 28 ft lbs. Put a couple bottles of Chevron Techron or Gumout with PEA in the gas tank to clean up the injectors.

 

Banks 1 and 2 too lean. Over the past few days I've removed the MAF and hit it with some cleaner, and also hit the throttle body and air intake with some CRC cleaner. It's a K&N filter, which looks recently serviced, but I have a cleaning kit on hand for when the time comes. I did notice when I removed the intake tubing that the lip underneath was folded in on itself, so I suspect that wasn't a complete seal. Unfortunately, resetting it properly was not the easy/cheap fix.

So I'm working on the easy cleaning options as I get acquainted with the new truck first, and will start working on replacing parts.

 

If there was a leak in the intake tube between the MAF and the throttle body, that would cause a lean condition.

 

I'd ditch the K&N and put a paper filter in. The oil can foul the MAF and they let through more fine dust.

Check for a vacuum leak in the PCV elbow behind the intake. Use MOTORCRAFT spark plugs.

You need to remove the throttle body for a proper cleaning, pay attention to the EGR ports in the elbow, they carbon up heavily and become blocked.

 

So a bottle of Gumout with PEA actually seems to have gotten rid of the low idle, now it's a bit higher, with the occasional rev that comes in pairs.
Codes are as follows:
P0171: System Too Lean Bank 1
P0174: System Too Lean Bank 2
P1131: Generic DTC Code- No description available
P1151: Generic DTC Code- No description available

So I picked up four O2 sensors to get them all on the same page. Hopefully that's the fix, the MAF is next. Also did a little cosmetic work, really revitalizes the look.

Before.
After.

60 bucks well spent, even came with bulbs so nowf I have spares.
Something else annoying now- the odometer is intermittent, more often off than on these days. Research says I need to remove the data bank and do some soldering... which I don't have the tools for. Also seems like I have a minor leak in the rear window seal, noticed some dripping in the back seat during a rain storm.

 

The leak may be the third brake light. That seal usually needs some sealer. I would change the plugs, Motorcraft only, and torque to 28 ft lbs.

 

Intermittent odometer:

https://www.f150online.com/forums/ar...er-repair.html

You really don't need to replace the downstream O2's, but a fresh set of upstreams wouldn't hurt. Note that you should only use Motorcraft or Bosch sensors, Motorcraft preferred.

Your 1131 and 1151 are also lean codes both banks. You really do need to look for vacuum leaks, especially in the PCV elbow.

 

I'll have to ask around for someone with a soldering gun and I'll make that repair. I have Bosch sensors.

Is there another thread you can point me to for this? Something that doesn't involve a smoke machine? Thanks for all your tips so far guys!

 

Follow the PCV hose back from the PCV valve to the back of the intake. The elbow back there rots out.

Vacuum leaks can be found with an unlit propane torch. When you pass it over a leak, the idle will momentarily jump.