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(2000 Honda Odyssey)
in Atwater, CA on October 08, 2010
I have 2000 Honda Odyssey LX. The check engine light came on several months ago. I followed what the handbook said "after 2 or 3 gas tank fills it will go off" and it did - for a while. Then it would go out and come on intermittently. For the last month it has been on all the time.

The van runs great, but twice in the last 6 months it did not start, everything went dead, but it did start after leaving it for 10 minutes.

Went for smog and it failed, supposedly for codes P0401 (ERG flow insufficient), P1456 and P1457. The station said one of those codes was for computer, but in all his years working for Honda (he doesn't work there now, this was not a Honda dealer/station) he has only replaced 3 computers. He went ahead and replaced ERG VALVE (EGV658) and the AIR BYPASS VALVE (17310-SOX-A02).

It passed the smog test - but it cost $581.

After 200 miles of driving the LIGHT IS BACK ON.

I have read several site forums and will try injector/valve fluid, fill it with good gas (Shell) and disconnect/reconnect the diagnostic connector under the dash.

Is it possible that they replaced good parts in an effort to fix the problem or were those codes indicative of those parts?

I dread to think what a new computer
would be to replace. Anyone know the going rate? And can I change the computer myself?

Displaying 2 answers & 11 comments
Popular Answer
on October 08, 2010
It sounds like the shop isn't sure about what they are finding during their diagnosis, and that is not good. This needs to go to a shop that will diagnose this properly. Find a Gold Shield smog station and have them perform a diagnosis.
on October 09, 2010
Thanks bretb. I agree with your suggestion, but I have given this station $581 to fix it and not willing to go elsewhere without a solution
on October 09, 2010
I have been looking for the diagnostic connector to disconnect it. I believe it is under the dash to the right of the driver at knee height, but there is a lot of stuff there. Can you or anyone describe what it looks like. Thanks a million.
on October 08, 2010
Sounds frustrating. I'm sorry you are having the experience you are.

P0401 is indeed insufficient EGR flow. But P1456 and P1457 are Evaporative Emission system leaks that do not appear to have ever been addressed, by your account.

Have you had the starting problem lately, or is that part solved? If it is solved, the air bypass valve probably helped you there. The EGR valve probably fixed the P0401 (unless it has returned...pull codes and find out...).

But the P1456 and P1457 would be there for detecting leaks in the Evaporative Emissions system, and should be pursued.

Probably will not need a "new computer"...
on October 09, 2010
Good information DaveJHM - I have noted your comments about unaddressed problem codes and have called the station this morning. The guy who dealt with problem off til Tuesday but I put over my case and that I am not prepared to pay more money for another diagnostic test. I was very nice about it but adamant it needs further checking. You know what they say "sugar catches more flies than vinegar" . . . for now. lol. Inside I am very frustrated.
on October 09, 2010
I have been looking for the diagnostic connector to disconnect it. I believe it is under the dash to the right of the driver at knee height, but there is a lot of stuff there. Can you or anyone describe what it looks like. Thanks a million.
on October 09, 2010

Hopefully they will re-check the codes for free at least. In the meantime, don't bother trying to clear the light, as doing so may erase good clues. You are absoutely right about being "nice about it but adamant...". As a director of a repair staff, the people I want to help the least are people that scream and yell and are not rational. Those who are reasonable and have good evidence get my attention. Mistakes can happen. They probably had the intent of getting your stall issue fixed and your vehicle through smog -- without further costly Evaporative Emissions diagnosis and repairs. Evap codes may not come back right away, and as long as they clear the "drive cycle" without the codes resetting, they can get it through smog. However, if you have no luck, the BAR (Bureau of Automotive Repair) in California may be interested in hearing that the smog station knowingly cleared evap codes, passed the vehicle through smog testing, and now they are back on...

Not that you have to go that far.

Hopefully good communication and sensibility will prevail. Do keep us up to date on your issue - I'd love to know how it plays out. Good luck.
on October 11, 2010
Hi Dave
Took the van back Monday. By the way the van has 108,007 miles. No problems of nonstart for months.

I was initially holding back the information you gave me on codes P1456 and P1457 being Evap Emiss system leaks. Was waiting till they came back with new diagnosis.

However, they wanted to charge me another $89.95 for further diagnosis, so I had to tell them that previous codes had not been addressed. I said "according to Honda . . .". Sorry, I twisted the source a bit.

Anyway, I got a call about 2 hours later, the latest problem: (including the same codes as before minus code P1456)


Cost to repair - Breakdown
PCM $1008.10
Reprogram PCM $190
PCM Removed and Replaced $89.95 (interesting this is the same price of the diagnostic text that I just got for free)
and the rest in tax, comes to TOTAL $1371.22

Given that I have paid $581.21 for EGR Valve and Bypass Valve replacement and the fact that that included $302.13 for labor to get to that difficult part of the engine and they need to revisit it again, what are your thoughts? I think you said codes direct to a general area and further testing gains definitive results instead of the dreaded new computer lol.

They have gone straight for renewing the computer.

I told them that I do not want them to fix the problem and need a second opinion.

What are the dangers of running the van with the latest problem till I decide (with your professional advice greatly appreciated) what avenue to take?

Is it worth mentioning that Honda recalled this van and replaced the automatic transmission a couple years ago in a class action? Only mention this because I am Googling to get a price for a new computer and have found several sites complaining about Power Train failing in 2000 Honda, quote "Failing Component:
Power Train:Automatic Transmission" I take it the computer serves more than the exhaust emissions?

Oh, it gets more of a minefield lol.

on October 11, 2010

I could have a strong opinion on this, but to be professional, I will stick with facts.

First, I strongly recommend a second opinion. You may want to speak with the shop manager/owner and communicate your dissatisfaction with the thought that you will be seeking a second opinion, and if in fact it disagrees with their diagnosis, you will be seeking a full refund or complimentary repair, whichever is favorable. You can back this up with the fact that the Department of Consumer Affairs (Bureau of Automotive Repair - BAR) in California will absolutely support the consumer in valid cases (as yours may turn out to be) and can make it very difficult for folks with smog licenses that somehow get a vehicle to pass smog while having recurring failure codes.

I find it interesting that they still did not address the Evap code(s).

My gut feeling is that they are guessing at the PCM...but I cannot examine the car obviously and that is why a second opinion will be valuable.

To restate - Codes (like P0401 and P1457) only give reference to a specific event that occured historically, or one that is actively occuring. The nature of your codes, based on the ones that are coming up, speaks to events that occured during the course of driving or running the car. P0401 cannot happen with the key on and engine off as a hard fault. Thus, I would find it impossible for a P0401 to be a result of anything other than an intermittent failure. At least intermittent in the fact that it does not happen with the engine off, obviously. So, a "defective PCM" damaged by a shorted part would be defective constantly, not just for EGR flow.

Sure, you could have a failed PCM. It does happen. Just not terribly often.

Dangers of running the van: something in the evaporative emission system is leaking, causing issues with fuel vapors being contained. Not a deal breaker to drive, but not the best idea for emissions. Plus, under extreme circumstances, additional parts may fail due to a lack of repair. The could have running issues, but it appears you are not having any perceptable issues driving the vehicle. So, you could probably buy a little time there too.

Still, I would get that second opinion and resolve your concerns before it ages further. Good luck and keep us informed.

UPDATE -- oops, looks like you've just added further thoughts -- to address:

The transmission is unrelated to your PCM issues. And vice-versa. Honda extended the warranty on the transmission due to longevity concerns in the class action suit. Good for you that you were able to benefit from that prior to expiration.

Yes, the PCM is the central processing point for all the electronic engine and transmissoin controls, including but not limited to emission controls, spark, fuel, air strategies, transmission strategies of shift points based on throttle desired and vehicle speed, etc.
on October 12, 2010

Thanks for all this information. I need to go to another station, preferably a Gold Shield. Will I be upfront with previous codes, information and costs or let them test with open mind?

Thanks again
on October 12, 2010

Your choice really. Probably it is best to lay everything out on the line - including sharing repair orders, invoices, etc from your experience. More info is better to get a clear and valid diagnosis. Gold shield station...or even Honda dealership with a senior master certified tech would be a great choice.
on October 25, 2010

I have been unable to do anything over last 2 weeks due to prior arrangements. This coming week I intend to see this problem through, so I am not being ignorant by not posting what's going on, just that nothing has happened to date. There is a Honda dealership in Merced and also several Gold Shield stations, so it it just a matter of me hooking up with them. There seems to be so much to tell them about the sequence of events, I hope I can find a technician who will listen to what I have to say and follow your train of thought (if I can convey it properly) and just not hear that I want a diagnostic check. To tell you the truth I am dreading the process - lol. Will get back to you asap with news.
on December 20, 2010
i am having a simular smog repair issueeon a 2000 civic, mine error codes registers
issue with incomplete combustion in 1st cylinder. Smogg emmision swhere high but below limits. does this sound like aplugged fule injector or a bad spark plug?
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