Accord Gen7 2.4 Idle and P0172

[eltax91]

Hi folks

My daily snotter is a gen 7 2.4 accord with 173k under it's belt. recently it's had a slightly rough idle from cold starts. last 2 days, a very rough, almost going to stall idle on cold starts. If you slip it out of Drive into Neutral (it's an auto) then idle picks back up from 600rpm to 950rpm and is ok. Select drive whilst stationary and it's about to stall again.

On my return from the station today it's thrown the CEL. Scanned it with torque and it's a "P0172 - Too rich" fault code.

Google gives millions of reasons. MAF, MAP, vacuum leak, even old fashioned valve clearances. I did change the MAF, plugs and all 4 coil packs on 155k when i got a CEL with a code that was pointing at just the MAF and some rough running issues.

So, perceived wisdom on here? Where do i start diagnosing the issue? Any advice gratefully received, the information out there is wide and varied, so much so it's almost as confusing as no info at all!

[E-bmw]

As it is an auto a good start is always going to be a fluid & filter change for the 'box.

Having said that it sounds likely to be an air leak into the inlet after the MAF causing the ECU to compensate & falsely richen the mixture.

If you can't see/hear anything try spraying carb cleaner/brake cleaner/wd 40 at it where there are likely candidates for leak points & if you hear an engine note change look closer.

[Stu78]

Had years of Accord 2.4 ownership and participating on the Accord forums and it's very unusual to hear/read about problems with the K24 and I don't recall that code ever coming up. Have a search on TypeAccord and Honda Karma.

[eltax91]

Stu78 said:

Had years of Accord 2.4 ownership and participating on the Accord forums and it's very unusual to hear/read about problems with the K24 and I don't recall that code ever coming up. Have a search on TypeAccord and Honda Karma.

I’m a Honda karma member and had a good search. I pulled all the plugs tonight, all clean. I don’t suspect fielding anyway, the car is has converted and it’s equally poor on both.

I checked the air filter, no blockages and clean as a whistle. I found the clip that holds the intake to the throttle body was not secure and loose so replaced that. Also the sensor in the pipe between TB and airbox could be twisted. There’s no room for a jubilee so I’ve put some temporary hylamar blue on it to hold it steady and see if that’s the issue.

Will see how tomorrow’s cold start is.

[eltax91]

Ran it this morning. Ever so slight improvement in the idle but not fixed by any means.

Had a screaming two year old for the nursery run so turned the radio off. After dropping her off, at idle and only in drive, not in P or N, I can hear the faintest of whines from under the back seat.

Suspect in-tank lift pump is either causing or not helping the issue.

Anyone know how hard it is to change? Or even better, a part number.

[Stu78]

Is your a saloon or estate? On the estate it was under the rear bench, I just did the filter but it's all one unit with the pump built in. Was easy to change, I got the part from Holdcroft.

[eltax91]

Stu78 said:

Is your a saloon or estate? On the estate it was under the rear bench, I just did the filter but it's all one unit with the pump built in. Was easy to change, I got the part from Holdcroft.

Tourer yes. I’ll see how eye watering lot expensive the pump/ filter is from them

[Stu78]

From memory I think there's a balancing act when you fold the seats down and lift the base up, you sort of need to be in the middle of the movement. When you pull the carpet up it's obvious. Of course try to do it with low fuel, battery disconnected, fuel cap off. My filter was absolutely stuffed at 120k though I didn't notice any change in performance after I changed it! Think I paid around £40 for the filter but that was four years a go, not sure how much the full unit will be. If you contact Holdcroft don't forget to mention you're a member of Honda Karma, you'll get a discount and free postage.

[eltax91]

Stu78 said:

From memory I think there's a balancing act when you fold the seats down and lift the base up, you sort of need to be in the middle of the movement. When you pull the carpet up it's obvious. Of course try to do it with low fuel, battery disconnected, fuel cap off. My filter was absolutely stuffed at 120k though I didn't notice any change in performance after I changed it! Think I paid around £40 for the filter but that was four years a go, not sure how much the full unit will be. If you contact Holdcroft don't forget to mention you're a member of Honda Karma, you'll get a discount and free postage.

Thanks, good info. I've not seen the price yet, but i think the pump is in the hundreds of pounds territory. I wonder if i might try the filter first and see if that's my issue. but with the slight pump whine i'm not hopeful

[Stu78]

Why not get a used unit off ebay, I'll have the code somewhere.

edit: 17708-SEA-E01, there's model year extra digits but pretty sure that's the code.

Edited by Stu78 on Wednesday 3rd July 15:40

[eltax91]

Stu78 said:

Why not get a used unit off ebay, I'll have the code somewhere.

edit: 17708-SEA-E01, there's model year extra digits but pretty sure that's the code.

Edited by Stu78 on Wednesday 3rd July 15:40

Thanks. I had considered it. I will get to the pump tomorrow, double check the part code and then start the hunt.

Car is still running for now!