03AccordEX

Hello everyone, my name is Rick and this is my first post here. I would like to begin by thanking you for reading this and for hopefully helping me out here. I need all the help I can get as I'm unemployed and need to fix this myself.

Took my car to AAMCO for a free code read as my check engine light is on and I need to get the car smogged before the 14th of this month. The guy gave me these three codes below...


P0134- 02 Circuit, NO activity detected, bank #1 sensor #1

P0325- Knock sensor, #1 circuit bank #1

P2251- 02 sensor, negative current control circuit, open bank #1 sensor #1


Thank you,
Rick

redbull-1

P0134 and P2251 is related to the rear Air Fuel (A/F) Ratio Sensor. If these were your only codes, I would have probably said that sensor needs to be replaced.

However, since you have P0325, which is the knock sensor, it may be due to rodent (e.g., rat) chew of the wire harnesses. Honda has an upgraded knock sensor harness with protective sheathing due to this very reason. It is common for rats to crawl in that warm space where your knock sensor is, on your generation Accord V6.

03AccordEX

Hey REDBULL, thank you for your reply! I suppose the knock sensor or the wires there need replacing huh?

redbull-1

The knock sensor wire needs to be replace, Honda sells an upgraded wire harness. But, if you are watching your money, you might see if you can repair it for now. The rats may have possibly also chewed on the rear A/F sensor wiring too, as that sensor wiring should be near the middle of the engine.

It is not easy to get to the knock sensor wiring though.

redbull-1

These may help you. One guy bought the knock sensor sub-harness for $7.

http://www.driveaccord.net/forums/sh...d.php?p=328556

https://honda-tech.com/forums/honda-accord-crosstour-2003-2012-118/cel-diagnosis-help-p0325-03-accord-v6-2385490/

03AccordEX

Wow looks like a lot of work!!! REDBULL, you're awsome, thank you very much for your help.....

redbull-1

It is a lot of work. If I remember correctly, someone posted at some site before, they were able to disconnect and replace the knock sensor sub-harness with a pair of long needle-nose pliers without taking everything else off; only a few things.

One other thing, the AF ratio sensor may still need to be replace if it isn't the wiring though.

KWayRacing

Yeah I would def. suspect rodent damage. You can fish the connector out of there but usually end up braking the knock sensor trying. You can easily break it even doing it the "right" way. They are extemely brittle. The subharness is cheap. Cheaper to buy than to think about repair most often. The p0134 and 2251 are indeed rear clyinder bank AFR codes. I would follow that sensor's wires and verify the pesky varmit did not get a hold of that harness also. If that sensor is faulty they are not cheap and I am not sure they are available aftermarket? If I remember correctly the front and rear cylinder bank AFRs are the same part, Although they have different part numbers. The clip/stay that comes on the harness on the front one is what makes them different part numbers. You could easily compare wire color/ cavity # to verify. The reason I mention this is because to verify you could swap them, clear codes, then rescan for Front AFR code. Also, A small salvage/rebuild yard may be more inclined to sell you the front one for ease of removal. I am referring to the upper sensors in the manifold. The lower sensors are older style 02 sensors that only monitor the catalytic converter's performance. Either way good luck.

03AccordEX

KWAY, excellent idea, thank you for your input I really appreciate it!

03AccordEX

Update: 12-10-09

I searched everywhere for the best price on parts and I ordered all my parts online from a place called HondaPartsNow.com which is a real dealership in North Hollywood California.
I ordered the knock sensor wire harness, #1 O2 sensor, gaskets and new spark plugs for good measure. Turns out the advice I received here was accurate on the knock sensor harness as it was definately just laying there unattached.

I just installed everything, pulled the fuse and it runs fine with no CEL.
I need to drive it for a few drive cycles and take it in for smog. For now though, I would like to thank you for your help and advice thus far!

Best regards,
Rick Burnett

KWayRacing

Glad to hear it is smog ready. Good job on the work and posting back. This is how Honda Tech works.

Little Blue

Hello, I have a 2006 Honda CRV and had the same problem with knock sensor. Light never came on though. Vehicle just started sputtering and stopped. Took it to dealer and found that indeed rodents had chewed the wires. Honda repaired it with shrink wrap and I was good to go. Now, 5 years later check engine light has been on and off for months. Code is 0325 knock sensor again. And it does feel like vehicle is going to quit on me as it struggles for power and does it's hop, skip and jump thing. I guess it's time to replace that wiring huh? Any idea what that's going to cost me. I'm not funded for car expenses right now. That's why it's gone on as long as it has. Thanks.