P0171 and P0174

[sanjoin]

2003 V6 S-type with ZF in it.

check engine light came on for no reason. read the codes - gave me the P0171 - Engine Lean and the P0174 - Engine Lean (bank 2).  Why? What is it? Sometimes car jerks going from 1st to 2nd - like once every other day. Drive it every day, puttin about 50 miles on it.

Please help with any info or advice. Appreciated.

[sanjoin]

forgot 1 more thing: it also shows a yellow warning saying "restricted performance" .  also jerking seems to appear on cold car. when it warms up everything fine.

[sanjoin]

fixed! it was just a minor vacuum leak, easy fix. jag is pretty smart =)

[Neil]

Glad to hear you fixed it.
was it a breather elbow (lower) ?

[jackdotnet]

damn shame he hasn't responded...I have exactly the same codes and am completely stumped...

[Neil]

Check if you have cracked upper elbow.....

[jackdotnet]

hmmm....cracked upper elbow...are you referring to the breather line from PCV on the right hand bank to throttle or what...by the way I have checked for vacumm leak using carb cleaner and propane and there doesn't appear to be a leak...however I'm not a mechanic...just handy....sometimes.

Jack

[sanjoin]

hey, sry, im back on again ).. it was a vac leak from a little rubber hose and it was right there on the top of the engine to the left a little, amaizing how i didnt see it from the very beginning. sry i cant describe it any better.