Honda Odyssey Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
61 Posts
Discussion Starter #1 (Edited)
'01 Odyssey, 125K miles. There is hesitation when climbing hills: The engine rpm stays at some 3500 rpm, even when the gas pedal is pressed further, then the CEL flashes due to misfiring. The problem seems to be getting worse over the last few thousand miles and it seems to be worst when the car is warm. It seemed to have started after we heard broken catalyst material in the converter (not loose shields, I checked) several months ago. Low-speed driving is fine. The CEL came on with P030x, and later with P1399. Also P0420 has occurred intermittently.

Is it almost certainly the cat? I'm in California and cannot find any suitable aftermarket cats online, so I may have to go to the Honda dealership and it'll cost a bundle. (And why would the cat fail at only 125K miles?)

Could it be a clogged EGR port? There are no problems at lower speeds and I have not gotten a code for the EGR.

Could it be the fuel filter/pump? Elsewhere on this forum the filter has been deemed to be a 'lifetime' part not needing replacement except at very high mileage.

Thanks for suggestions.
 

·
Registered
Joined
·
2,892 Posts
Try inspecting and/or replacing the sparkplugs (you can even use the cheaper NGK V-groove plugs).
Have you tried using an injector cleaner such as Techron or SeaFoam or similar.
Both of the above will only cost around $20 and a little of your time.
Don't know about the EGR or how to better check the Cat.
Buffalo4
 

·
Registered
Joined
·
3,163 Posts
P1399 is a temporary code for Po3xx codes. There should be other codes P03xx. The converter code may be result of too much unberned fuel being sent to the exhaust. It isn't caused by the EGR either. Have all the codes pulled from the computer. If a P03xx code hasn't surfaced it will soon. You may also have a converter problem but it is separate from the P1399.
 

·
Registered
Joined
·
61 Posts
Discussion Starter #5 (Edited)
Thanks for these suggestions. I replaced all the spark plugs a couple months ago with NGKs but haven't done anything with the coil packs or injectors. I'll try some fuel injector cleaner as it's cheap and fairly easy.

I had thought the P1399 would result from a clogged catalytic converter, which creates high exhaust back pressure. I had previously had random misfires without P1399 on one other occasion, where the van had trouble climbing a long hill several months ago. A few months before that, some catalyst material broke free inside the converter, suggesting it was breaking down and becoming clogged.

The EGR port cleaning looks doable and I may try that.

I will try some of these things out and hopefully a solution will present itself.
 

·
Registered
Joined
·
3 Posts
wormguy said:
'01 Odyssey, 125K miles. There is hesitation when climbing hills: The engine rpm stays at some 3500 rpm, even when the gas pedal is pressed further, then the CEL flashes due to misfiring. The problem seems to be getting worse over the last few thousand miles and it seems to be worst when the car is warm. It seemed to have started after we heard broken catalyst material in the converter (not loose shields, I checked) several months ago. Low-speed driving is fine. The CEL came on with P030x, and later with P1399. Also P0420 has occurred intermittently.

Is it almost certainly the cat? I'm in California and cannot find any suitable aftermarket cats online, so I may have to go to the Honda dealership and it'll cost a bundle. (And why would the cat fail at only 125K miles?)

Could it be a clogged EGR port? There are no problems at lower speeds and I have not gotten a code for the EGR.

Could it be the fuel filter/pump? Elsewhere on this forum the filter has been deemed to be a 'lifetime' part not needing replacement except at very high mileage.

Thanks for suggestions.
I don't know about the '01 Odyssey, but I have my friend whose very expert on that car. I will ask him about that car. I will just PM you. :D
 

·
Registered
Joined
·
3,163 Posts
When you ignore fixing problems as they show up you wind up with the problems the op has. You are looking for a single cause of the problem when you actually have multiple problems. You have to diagnose each problem separately.
 

·
Registered
Joined
·
61 Posts
Discussion Starter #8
Problem solved - it was a plugged catalytic converter.

I bought a new catalytic converter from Majestic Honda and had it installed at a local muffler/brake shop. Because it was also due, I had an emissions test performed. The vehicle passed but clearly the NOx emissions were higher than they should be (230 ppm at 15 mph and 600 ppm at 25 mph, both should be <20). As the catalytic converter is new, this points directly to a partially obstructed EGR port. The hydrocarbons were fine (<4 ppm) and the %CO was 0.00 at 15 mph and 25 mph. These readings suggest the car's air/fuel mixture is fine, so any severe problem that might have caused the demise of the converter is not detectable at this level. (I was expecting a highly rich condition, for example, which might have shown as high HC.)

When driving home, however, the sluggishness and hesitation problem when climbing hills is completely gone!

Since the only part changed was the catalytic converter, this must have been partially plugged and causing an exhaust obstruction. I looked inside it and couldn't see anything obvious, but I could look only at each end of the catalyst material.

I now have the replacement gaskets I need to do the EGR port cleaning job. With the hesitation problem gone, the EGR port cleaning seems less of a worry for the moment.
 

·
Registered
Joined
·
19 Posts
Dead post I know but was my same issue glad I found it ..... you can test it as well if you remove the front o2 sensor ...will be loud but good for testing
 
1 - 9 of 9 Posts
Top