New to this forum and having BIG problem with P0171/P0174

[ewillis]

It looks like there are some knowledgable Ford guys here................I hope so!

I have been having an issue with the P0171/P0174 codes for a while now. I started trying to resolve this before the summer but got too busy and left it. Now the wife is back at work (school) and driving the sport trac daily again. Hers is a 2003 Sport Trac XLT, Non-Flex Fuel.

Codes popped-up right before it was due for oil/ oil filter/ air filter/ fuel filter change. I thought this work would fix problem but didn't. On another forum I was told the problem was DPFE. Spent $125 and still not fixed. I grabbed a can of carb cleaner and sprayed all around the intake and vacuum lines I could find but did not find any noticable vacuum leak. I checked the fuel pressure and have 66 PSI with no fluctuation upon being revved-up.

The light being on doesn't bother me and it has no noticable effect when driving down the highway but the problem is that it doesn't want to idle sometimes. It doesn't happen every time I stop but sometimes the idle gets so bad that it starts loping and will eventually cut off if I don't rev it up some. Last night, It actually started skipping when I pulled off from a stop light (first time it has done this!) The skipping cleared up quickly, but obviously what ever is wrong is getting worse!

Any help certainly appreciated!

Ernie

 

[BeastMode843]

Hey Ernie, i am having this same problem. so maybe you can try what i have done and i will try what you have done. worth a shot i guess. I have cleaned the MAF with no result, used better gas (93) no result, used Lucas fuel treatment no result, used a heavyer oil no result and changed the 02 sensers worked for a while. I was just told it may be the cassettes. good luck

 

[ewillis]

I finally found mine! I don't know the part name but it was the big vacuum line running from the front of the intake manifold, taking a 90 degree turn and going back towards the rear of the engine on the passenger side. The 90 degree elbow on the front had a crack/dry rot in it. I had done a visual on this before AND sprayed over it with carb cleaner but the crack turned out to be on the BOTTOM side of the elbow. With it there, I didn't see it and the carb cleaner didn't affect the idle. I reset the Check Engine Light and have driven it since Saturday afternoon with no issues. It's had this issue since about April of this year and I had forgotten how good it actually ran!

Good Luck with yours!

Ernie

 

[tringham]

thanks

 

[ncranchero]

Sorry for the delayed response, been AWOL for a few days. There's a sticky at the top of the page that deals with these two codes.

http://www.explorerforum.com/forums/showthread.php?t=314670

 

[MidnightRebel07]

Yesterday must have been the day for digging up old dead threads, lol. Let me go see which one I can dig up. LOL