So I ran into this problem on our 2006 Kia Sedona, it had been running a little off and was hesitating at idle. The check engine light came on so I pulled the ODBII codes. I got two codes, P0171 (Bank 1 too lean) and P0174 (Bank 2 too lean). Now since this issue is affecting both banks, it had to be something that was common to both. Too lean typically indicates that it is getting too much air or not enough fuel. I did a little bit of looking around and quickly found the problem.
I started looking and quickly found the air intake hose was cracked at the flexible section. This appears to be a fairly common issue on the Kia Sedona and possibly other similar vehicles. As this hose gets some age on it, it gets hard and brittle. Every time you check the air intake filter you flex this hose and eventually it cracks. The reason for these two codes (P0171 and P0174) is that this hose is after the MAF sensor. The computer has already taken it’s reading of how much air is flowing through the intake and has adjusted the fuel to correspond. With this hose cracked it allows more air into the engine than the computer thinks is getting there causing a lean condition.
Replacing this hose is quite easy, it took me about 30 minutes from start to finish. It’s five clamps to get it swapped out. The replacement from Amazon comes with an adapter for the forward reservoir if yours is the smaller one. Just keep in mind that you will need a larger clamp that does not come with the replacement. You can use a standard worm clamp to get the job done.
Good luck and hope this helps!
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