I had the oil changed on Thursday. Saturday morning, (two days later) my 2004 Accord, 4 cyl started throwing a P0171 error code.

I've read elsewhere (https://honda-tech.com/forums/showth...ighlight=p0171) that when messing with the Air Filter, sometimes they disconnect the PCV which can cause the P0171 code. The shop manager showed me the Air Filter but didn't change it.

If it is the PCV, what should I look for and how would I reconnect it?

 

look at the intake tube you will see it un hooked or loose half way up the tube

 

I took a look in the engine compartment and noticed that the Air Flow Chamber (item 2 on the air cleaner pdf) was not connected properly, the bottom connection was sort of connected, but the upper connection was NOT connected at all. Could this have caused the P0171 error?

I've reconnected both the connections and ran the engine for about a minute, but the Check Engine Light is still displayed. Do I have to run the engine longer, or is there a method to clear the Check Engine Light?

Thanks for any help.

 

Try disconnecting the battery for a while first to get the code to reset. Then, start it up and it see if it comes back on again.

 

Usually you can pull the ECU fuse in the under-hood relay/fuse box. Make sure ignition is off, pull fuse for 1 minute, replace, turn on car. Your fuel mileage will go down until it builds up a memory but should pick back up in 100 miles or so.

 

I was reading about the pulling the radio fuse as well. Does this actually work?

 

THe diconnected tube was the problem. Just keep driving it it will go off or disconnect neg. battery cable to reset light.

 

Yup, just like you said, the CEL went out after driving it (over 20 miles). Don't know if it was the amount of driving, or the number of starts, but the light is off now. Thanks for the info.

Now to tell off the Valvoline Oil Change manager!

 

I have similar issue on 2004 accord 166k miles. Flex pipe needed replacement had it welded several times and just recently replaced with new. Error code comes up approx. 35 miles after reset of code. Could it be something from the welds / replacement is causing sensors in exhaust to read incorrectly? And if so how to clean?