any body who can help?

I ran my computer diag. last night. Error code p0171 - "System too lean (Bank No 1) " and P0455 "Evaporative Emission Control system leak (Gross Leak)." SO I got the codes, but what the heck do they tell me? In addition, I tested the emmisions and the test came back and failed on one " - $25 Evaporative maximum Vapor geration rise limit Phase 4 is -64.00 Limit phase inches of water w/minimum limit 1.50 Has FAILED."

Can any one help deciver the code???

 

your 455 and failing the emission test are the same problem. Its got a leak on a vapor line somewhere. All i can tell you is bring it in to a dealership and let them find it with the smoke machine.

the 171 could be because of a AC drain tube problem if it is in a 5.4 truck. If so, the AC condensate has dripped on the bank 1 O2 enough to kill it. (cold water drops on a heated piece of ceramic)

 

Thanks for your comments. It is a 5.4L alright. so you think it may be due to a leak on the O2 sensor? I have a slow leak coming out of the radiator, but the O2 sensor is on the exhaust line right? Any additional info is welcome!

-thanks

 

The P0455 could be a loose or broken gas cap. Check and make sure the gas cap is tight then clear the codes and see if it comes back. The P0171 is most likely a bad o2 sensor but could also be other things. So now you have a choice - throw an 02 sensor at it and see if it works, or pay a dealer to hook up his scan tool and see what the sensor is doing.


-Jon

 

thanks guys, any other input?

 

jpreppy,

Did you ever clear the P0455 code, or replace the fuel cap?
Just courious. I just pulled the same code out of my 98 expo.
I reset it.....we'll see....

 

PO171 was a bad MAF on my 98 4.6 liter. It threw that code, I cleaned it, and it seemed to work. Two weeks later it threw the same code, and again it was the MAF. It was just a warning the first time I guess. I got the system lean bank one also. Good luck fixing it!!,,,,98