P0171 and P0174 codes

[jpexplodersport]

I have a 2000 Explorer Sport. For the past 3 months these 2 codes come up together. I already checked the MAF sensor and even swapped it with one that works and I get the same codes. After I reset the engine light it will come back on after about 100 to 400 miles with the same codes. I have freeze frame data also if it will help.

 

[Cobraguy]

I'm not sure why you are replacing the MAF sensor for those codes. Those are lean codes...one for each bank. Look for a vacuum leak or check for poor performing O2 sensors.

 

[jpexplodersport]

A bad MAF sensor could cause any car to run lean. I highly doubt both my O2 sensors are bad at the same time especially when one of them are new. I also thought it might be a vacuum leak but so far I haven't been able to find one.

 

[team]

if you have an ohc motor it may be the intake gasket o rings

 

[jpexplodersport]

No one has or has had this problem before?

 

[Tbars4]

...If you do a quick search with those code numbers you will find that several people have had this problem and you will also find the answers you seek...

...Searching always leads to quick answers...:biggthump

 

[CAHUNTERMAN]

if you have an ohc motor it may be the intake gasket o rings

The OHV motor is prone to intake manifold leaks as well. I had the same codes and it was the lower intake gasket causing the leak.

 

[team]

The OHV motor is prone to intake manifold leaks as well. I had the same codes and it was the lower intake gasket causing the leak.

yes, but the OHC motor actually had a TSB about this from ford, it is definitely more prevalent in the OHC motor

 

[CAHUNTERMAN]

yes, but the OHC motor actually had a TSB about this from ford, it is definitely more prevalent in the OHC motor

Yes, I think that TSB on the OHC is where I got the procedure to use propane and monitor the O2's to determine where the leak was, but it's been several years since I did it so I may not be remembering correctly.

 

[jpexplodersport]

I was thinking it was an intake leak because I heard it was common in the ohc motors but everytime these codes get set the motor has reached normal operating temp and I thought if it was the intake it would do it when it was cold. Also to let everyone know my gas mileage is still good and the truck actually runs good. Idle is nice and smooth too.

 

[jpexplodersport]

http://www.aa1car.com/library/ford_lean_codes.htm. This link is for cobraguy.

 

[Cobraguy]

LOL

I think I have a handle on lean codes. The MAF isn't the first place I would look on this motor...as has been suggested. KISS is a very viable procedure. MAF would give indications too....nevermind. Your new and haven't been around here.

 

[JOEZ33]

I was randomly getting each of those codes, every few days. The truck felt fine but randomly got one or the other codes. I found a loose hose. This hose is pretty hard to find. It is actually three hoses that TEE together under the throttle body area. One hose goes to the driver's side plastic intake and the other goes to the pass side intake, then they TEE together under the throttle body. From there it's one long hose which goes around the water pump, aft of the belts so you can't really see it. I believe it ends up going to the evap canister. Mine was loose where they all tee together, causing intake leak to both driver/pass sides of the plastic intake manifold.

 

[BrooklynBay]

This link is in # 51 in my list of useful threads: http://www.explorerforum.com/forums/showthread.php?t=177975

 

[jpexplodersport]

Thanks I'll check that hose tomorrow. I just cleared the codes again with my scanner and I drove from Ma to Pa, almost 700 miles and no engine light but I haven't checked the pending codes yet. I will be surprised if there isn't any.