Hi guys, I'm hoping for some insight into this:

I've been reading some of the EGR port cleaning threads with interest -- I have a 2001 Accord EX 2.3 and it has an intermittent miss / general unresponsiveness at low rpms and partial throttle. I've done all the usual maintenance items (plugs, wires, o2 sensor, injector cleaner) but it still doesn't feel right.

A few searches online showed similar problems caused by dirty EGR valves and/or passages and ports. I have cleaned my EGR valve by hand (as best I could, I couldn't open it to clean like in the old vacuum-operated ones), but I haven't seen any way to get at the ports/passages as I have seen was possible in the 94-97 Accords..

I unplugged the connector from my EGR valve and the hesitation and numb response has gone almost completely away, so I'm really thinking this could be the cause; throttle tip-in now is quite sharp and there seems to be a lot more low end pull than before.

Is there a way to clean those ports and passages in this engine? I read that the newer intake manifolds have plugs you have to pull out to get access to clean the ports, but I don't see anything like that on mine. Did Honda redesign the EGR system to make it less prone to clogging and maybe also unserviceable?

Maybe I should try to do a better job of cleaning my EGR valve?

Thanks in advance!

 

Well, I think I have found and fixed the problem.

I pulled off the EGR valve while the car was running to determine if there was vacuum at the port from the intake manifold. There was plenty.

I got thinking about fuel pressure, and pulled the vacuum line off the manifold that goes to the fuel pressure regulator. It came off much more easily than I expected, and I could see that the end of the hose was a fair bit enlarged from its original size. It wasn't split or anything, but it seemed possible that it could be leaking some.

I put a piece of tubing I had lying around on there instead, secured the throttle body end with a twist tie (talk about your shadetree repair jobs!) and it feels much much better. Time will tell, but I think that was the problem. My long term fuel trim is now around -5 or so vs. -10 before.

I guess what was happening was that at closed throttle, when there's supposed to be full vacuum on that line causing the fuel pressure to be lowish, some of the vacuum was lost to the atmosphere and the fuel pressure was artificially high. Which in turn caused the O2 sensor to sense an over-rich mix, causing the ECM to lean it out, which caused the miss and poor response at throttle tip-in. That's my theory anyway.

Just thought I would follow-up in case it helps someone else.

Cheers!