GHR27937

Hi all, need a little help.
2000 Honda Accord EX, 2.3 Vtec, manual 5 speed trans.
Car is operating in limp mode with the CEL on, scanned, code P1149.
Thinking the O2 was bad I replaced it and found out that it's not an O2 but an air/fuel sensor.
Reset the computer, ran the car for more than 50 miles, and the CEL came back on. I knew changing the A/F sensor didn't fix the problem because it was still operating in limp mode, won't go over 3000 RPMs and have normal operating u till you go beyond half throttle, after that it sounds and feels like a clogged CAT.
I checked the timing belt and that's fine, didn't jump a tooth.
So I figured I need to check all the sensors to see what they are reading, but I can not find any list of what my sensors operating ranges should be. I have a scan tool that will allow me to take a freeze frame, however my son thought he was helping me when he unplugged the scanner prior to me saving the info. So now I need to start all over again.
Anyway... I am putting the timing covers back on and will run the car to get all the info. In the meantime I could use some help getting the specs for the sensors.
Thanks in advance for your help.
I hope I am posting this in the right location.
Anyone willing to email me that list may do so, or please tell me where I can find that info online... Thanks again everyone.

lazlong

Check connections at the sensor, the relay and the ECM/PCM, in that order.

GHR27937

Thanks for the reply, however your response is a little vague being that there are many sensors and a few relays... I have already checked the connectors by unplugging bad reconnecting them all. Not an easy task I might add... So now to the relay... Which relay are you referring to ?
If I could find a list of what my sensors operation ranges should be I could double check them all to see if there are all working as they should.

holmesnmanny

just pull the actual codes

GHR27937

UPDATE:
Cleared all codes... Ran car for about 35 miles or so... Still won't rev over 3000 RPM, Then the CEL came back on... The code is P0172 bank 1 too rich, with a pending code of P0170 fuel trim malfunction.
I have adjusted the Valves, Cleaned EGR, cleaned throttle body, checked and rechecked the connections on the sensors, checked for cracks and leaks in the exhaust, checked fuel regulator, checked all the vacuum lines for leaks and clogs, checked the return fuel line for leaks and clogs..... And Nothing ! Still have the same problem. No power beyond 1/2 throttle, and at 3000 RPM engine acts like it hit a rev limiter, bucks and stumbles like crazy. But the car will run fine otherwise... Takes forever to get up to 60 mph but as long as you keep the foot out of her and don't go over 3000 rpm she runs like normal...
Does anyone have any other suggestions ?
What is the computer seeing to cause these codes ?
The only thing I have yet to do and will be doing today is check and clean the injectors, will be soaking them over night in my sonic carb cleaner.
Note:
I have read in this forum about others having the same issues but no one has posted any results as to what the real issue was or what the remedy was. When I find out what is causing the problems should I be just as big a D**k and keep the answer to myself ?
No ! Because that's why most of us are hear in the first place !

Grandhustleman86

Wow you have really been thru alot man, I'd be looking at trying a new/used ECU just to try it and see how the car reacts. The ECU youd be looking for is a, 00-02 EX 5spd "37820-PAA-A03".

I Found about 6 on ebay in muntes. My local JY allowed me to return a ECU i tried out. I know its a little vague. But ECU malfunction W/O "CELs" gets overlooked alot in these cars. Any water damage?

Im keeping an eye on this thread for your final results. Hard to believe it but there are "Veteran" HT'rs that actually care and are intrested man.

GHR27937

Thanks for the reply and input. I tore apart the fuel injection yesterday, cleaned everything up and checked the ohm resistance and all are at 11.5 except one was at 11.8. Don't think that is my issue, did a compression check and all cylinders are the same at 125 psi. So that checkes out. Will be looking over the exhaust again and checking the cat next but as of right now I am Not finding anything that would be causing this so I guess you maybe correct in my needing an ECU. Will call around today and see if anyone has one that I can use to trobleshoot this... Will post any findings. And thanks for the part number.

lazlong

Have you checked fuel pressure? The download for your model I found was corrupted but, being a 4 cylinder I would assume 40-ish psi. If pressure is too high, replace the fuel pressure regulator. Cheaper to check that and replace the regulator, if bad, than getting a new ECU.

GHR27937

UPDATE !
Finally found the problem ! The catalytic converter honeycomb deteriorated and is rattling around inside the housing causing pieces to clog the remaining exhaust, although when I checked the out flow from the tail pipe it seemed normal however this was at idle, I was able to hove someone rev the engine and found the flow restricted and upon inspection of the cat found it to be the final cause. Disconnected the pipe after the cat and started the engine and was able to rev the engine beyond half throttle and the stumbling at 3000 went away. Hooked up professional shop auto diagnostic computer and the car was in fact going into limp mode, all caused by restricted exhaust.
Thanks for everyone's ideas and thoughts.
New cat and cat back exhaust system on order. Will post the final outcome after it's installed.