I'm requesting some advice about some issues I am currently having with my 99 Accord EX.
Issue#1: Check engine light: Two codes, can't remember their exact numbers but I can find out and post them later. Both codes point to the EGR valve. I cleaned the valve, No Joy. I replaced the valve and reset the system, and the check engine light came back on after 2 starts and about 15 miles of driving. My next plan is to change the O2 sensor.
Issue #2: Shaking/stuttering feeling when traveling at a low steady speed. In traffic, maintaining 20mph, it starts. As soon as I let off the gas and get backin it, itgoes away for a short time.
Issue#3: Shift point out of 2nd gear is at a higher rpm level. Seems to be slightly slipping, but not that badly. When running approximately 45mph, and I kick it down, the transmission slips before kicking down. Is this a clutch plate problem or a pressure switch circuitry problem.

The car has 160K on it, so it doesn't owe me a thing, but I would like to see 200K out of it. I drive it daily, 150 miles round trip and I check my gas mileage at every fill up and change the oil every 4k miles. 6 months ago I was getting 29mpg (with the check engine light). Now I am getting 25-26mpg (with the check engine light, the stuttering, and the transmission issues).

Thanks in advance for any advice or tips you can give me.

 

If you could post those codes that would help immensly however the transmission issue sounds more serious.... 98-02?? have horrible problems with the trannies and V6's, so bad in fact that there was a class action suit against honda about it. Your transmission is probably failing (how much longer it will last is anyone's guess) unless you've just got really low fluid. You can call honda of america on it and they may be able to help. Repair requires either a new one or a full rebuild. The shaking I would guess is related to your Check Engine Light

 

Does the 99 have the 4 EGR ports directly on the manifold to clean out?

If those weren't cleaned out, you would still get an EGR trouble code set. That might take care of issue one and two.

For issue three, do you change your transmission fluid regularly and use Honda ATF? Does the transmission fluid ever have anything abnormal when drained like metal shavings, etc.

Isn't there a screen that needs to be cleaned on the AT?

 

I was wondering that myself (the 4 ports thing) that sounds like the issue to me as well... Also when you check the fluid see if it's discolored or smells burnt - either of those things is bad - also don't flush the tranny, just drain and re-fill

 

My Honda only has a single rectangular EGR port. I cleaned it out the best I could without taking the manifold off. I had the codes written down on a piece of paper, but I stuck that piece of paper in a secure spot. So secure that I can't find it anymore. I'll have to run to AutoZone one evening and have them tell me what the codes are again. I do know both of them were specifically for the EGR Valve.

I bought the car when it had 72K miles on it. I changed the transmission fluid shortly after that. I changed it again around 130K miles. I haven't had the tranny flushed. I did dump a quart a fluid through it before putting the plug back in just to wash out any loose debri that might have been in there. There wasn't any noticable metal shavings at either of the fluid changes. I did not use the Honda specific tranny fluid. Could that cause issues? I don't know of any screen that could have been cleaned nor a filter to change. Another webiste mentioned pressure switches mounted onto the side of the tranny and that was the cause of alot of tranny problems. It stated that transmission repair shops were repairing trannys that didn't need to be repaired because it was only the pressure switches that were malfunctioning. Does anyone have feedback about the pressure switches?

I bought a Haynes manual to "assist" me in some of my repairs but I do not consider it to be the bible for repair, only a reference to "assist" me.

 

To clean the EGR passage on that car you need to split open the throttle body, and there is a port that will be plugged full of carbon soot.
You can sort of trace the porting from the EGR valve to the throttle body by the hump from the valve that is seen on top of the manifold.
I'll look for more detailed info when I get home this evening.

EDIT: 4 bolts and some misc. junk to get the top off the throttle body

 

P1491 ---> Twice

I used the link to that great website for DIY'ers posted by hondadude; THANKS,I found a very detailed description of an extended warranty notice for the clogged port on the intake manifold. He described the "single" EGR port needed drilled out and a tube placed into it. I did not do this but I did use a dril bit and carb cleaner and cleaned out this port. Yes, it was completely clogged. I disconnected the battery top reset the systemwhile I changed the oil and drove the car to town. Just like last time, after starting it three times and driving it about 15 miles, the check engine light came back on. I went to AutoZone and read the codes and it was P1491 twice.

That website that hondadude posted states this for P1491:
P1491 EGR Valve Lift Insufficient Detected

I've cleaned both sides of the port on the throttle body side. I've cleaned the port on the EGR valve side, but I haven't cleaned it all the way through and I've changed the EGR Valve. Is there a way to cleanit all the way through the porting to the EGR Valve?For example =coathangar? Or is there something else I should try?

Thanks again for your suggestions.