po171 and 174 codes
 

what is the cause of these codes lean bank 1 and 2 I hear heard check oil cap mass air flow sensor and check some hoses. Which hoses are they and where are the located? any think else it could be? 02 randger 4.0 liter.
Thanks
Conrad

There is a rubber elbow that connects to a log tube from under the throttle body to rear of engine. Elbow was crack replaced rubber elbow cleared codes and was fixed thanks all.

Could be a ton of things. Generally it's a leak in the intake, somewhere. Start by checking for anything loose on the intake, follow it to the engine looking for any holes, lose hoses, etc. Could be a bad intake manifold gasket, etc.
Just start looking for anything lose or disconnected first.

Thanks, Brian

dpfe sensor, other wise know as the egr flow sensor, thats what my 0174 was. and the 0171 code was because one of the elbows on my pcv hose was broken

Strakill did u replace the egr flow sensor?

Yea. It was like 36 dollars and that took care of the 174 code

DO NOT REPLACE ANY PARTS WITH THE EGR SYSTEM I WAS WAY WRONG WRONG WRONG

lol.
It is best not to just go replacing parts unless you have a good reason to suspect that part.

So any other ideas what it might be?

vacuum leak!! either from one of the many vacuum hoses or an intake gasket is leaking, like mentioned earlier. i had the exact problem, it was a cracked vacuum hose.

Do you have a K&N filter?

no paper filter I check the hoses when it stops raining

I'm with 01_ranger_4x4 on this one. Had the same codes about a year ago, and one of my vacuum lines was cracked. Replaced the line, cleared the codes, and they haven't appeared since.

It's a vacum leak. Check all your hoses for cracks.

a dirty maf sencer will cause them codes