Just reading over the forum here. it seems that everyone is getting the dual of the codes...I on the other hand am only get P0174 and not po171. I am about to take the Truck in the garage and check for a leak in the hoses..Ill post on here if the solution is the same as everyone else.

 

Fill your info in @ the top right corner under user CHP so we don't have to ask what model, year, engine size and so on...

One bank testing positive for lean can be a variety of things - Still the most common is that elbow or a leak in the PCV system. Usually it's not the MAF unless both banks test positive, but I would clean that as well.

Worst case scenario with that code will be a bad intake gasket.

 

Sorry, 2003 F-150 4.2ltr, Has a stepside. I talked to someone else that had this issue an a similar told me to remove the plastic compartment ontop of my manifold and look there.. i'm going to check it out today for any hose breaks.

 

Hey guys,
I too have been bitten by the 171 and 174 bug. I have replaced the following:
- pcv valve (passanger side valve cover)
- both pcv elbows (pcv valve and on the back of the throtle body)
-cleaned the MAF sesor
-sprayed brake cleaner on the intake, pcv valve seal, and Throttle Body (no increase in idle).

* I have cleared the code (w/reader) multiple times but they return. I was actually able to smog the truck today after 90 miles. On the way home the CEL came on.
-I have also noticed a lack of power (or wrong shift points) when towing up hill.
-When I turn the truck off, I hear a hissing sound under the hood. Not sure where it's coming from, maybe by the radiator area (normal?).

I would love to stop these codes and get the truck towing properly again.

Thanks in advance,

Andymaan

 

Andymaan
I am in same boat as you. While in the process of troubleshooting I also found my fuel pressure to be a lil on the low side changed filter and was still low so i crawled under there and put in a new fuel pump. It is better after the fuel pump but still won't idle right hey at least it does not die as often now.lol i have everything except the hissing sound or i don't notice cause of my k&n it always been a bit loud...


Any help on this one? thanks in advance

 

Ok here is a slight update. truck is still not running right and seems to be getting worse. since my last post i took iac of and and replaced it and cleaned throttle body. the truck runs much better when it runs but still getting the codes and rough idle/stalling. I have admitted defeat. I have a friend that is a long time ford mechanic at a local dealership. I called him about my problem i only do this as a last resort he listens to this stuff all day i hate to ask him. either today or tomorrow he is bringing home the official ford diagnostic laptop that they use at the dealership.

 

Hey Daffy,
I'm looking forward to your reply. I really wasn't motivated to work on the truck over the weekend. I really thought I had fixed the issue by replacing the pcv elbow

 

to trace vacuum leaks I spray brake cleaner around the engine, if the engines surges when you spray in a certain area, you have found your leaks. . . this is old skool and may cause fires. . be careful



DISCLAIMER: I am not responsible for above mentioned buring down of vehicle:santa:

 

lol @ Camarothatcould. surprized i didn't

Here is what i have done
1. cleaned mass air flow really nice
2. knocked mass air flow off bench and and cussed a lot
3. replaced mass air flow
4. hooked multimeter to o2 sensors. got some weird readings so replaced them.
5. sprayed engine down with so much starting fluid checking for leaks surprised did not cause a fire.
6. checked fuel pressure was on low side of ok.changed fuel filter.
7. rechecked fuel pressure low side of ok changed fuel pump. this really did make a difference runs much better, but did not fix current issue.
8. cussed a lot again.
9. cleaned throttle body and changed iac
10. cussed alot more this time
11. admitted defeat and called friend that is a mechanic at local dealer

 

Reset the computer by disconnecting the battery terminals. Hook the battery up and start up the truck. Take a spray bottle of water and spray around the motor, and see if it caused the idle to change. My guess is you have a vac leak. I'd have to see the truck myself

 

Where in Indiana???

 

I have these two codes right now, but its cause when removing my intake I bent my EGR tube and I think it broke down low. The EGR tube doesnt even get hot anymore up by the ERG valve, that cause these codes too. . but I aint in a hurry to fix it. . .

 

if it were not idleing like a harley when it is warm and stalling i would not worry too much bout it till warmer weather.

Hey Camarothatcould northwest indiana right next door to gary

 

I'm also kinda next to Gary. . . St. John

 

Hobart here