95 Accord Computer problem

Hi,
I have a 95 Honda Accord that started acting up a couple days ago.
It started with the car sputtering like it had missed or something. The check engine light came on and stayed on for a while. I decided to
take it to a mechanic. When I started it back up, the check engine light was out, and it did fine for about 3 miles or so. It sputtered again, the check engine light came back on, and as I was pulling into the parking lot the engine died.
The mechanic didn't get any faults out of the computer. I think that was because by the time he got to it and cranked it back up the fault had been reset.
They told me I needed a new battery and new battery cables because the battery was sending erroneous signals to the computer, "garbage in, garbage out" was the quote. The valve cover was leaking oil, so they replaced the valve cover, plugs, distributor cap and rotor, and the ignition cables.
After I left it was still doing the same thing. I've since replaced the battery, cleaned the brackets with baking soda, and removed as much corrosion as possible from the cables.
The voltages look good at the terminals and across the wires at the bracket base. Further driving tests revealed that once whatever fault occurs and brings the check engine light on, the RPM drops below normal. With the AC running the load is too much and the car dies. With the AC off it'll keep running, but idle RPM drops off to about 200. Accelerations with the check engine light on causes the car to sputter and lurch.
Short of changing out all the batter cables altogether, I don't know what to do next. It seems like the cables are sufficient, but I don't know if there's some kind of a fault in a ground cable, etc. The fault seems electrical since the engine runs fine, but idles low after the fault occurs.
Anybody have any experience with this kind of thing?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
| The mechanic didn't get any faults out of the computer. www.autozone.com/N,311791/initialAction,repairGuide/shopping/vehicleSelect4.htm can tell you how to extract & interpret error code
| battery was sending erroneous signals to the computer impossible
| With the AC running the load is too much and the car dies. car cannot die, engine can stall, chk EACV
| idle RPM drops off to about 200 incr idle rpm
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It could be the battery - I had that happen in a Nissan once - but I'd think you'd have at least occasional trouble cranking the engine. If the battery isn't so new as to be valuable replacement sounds like a good place to start. Alternatively, if the battery isn't near replacement time now maybe you have another car you can swap batteries with. Finally, a digital voltmeter to measure AC across the battery terminals when it is misbehaving will tell the story. Caveat: a bad alternator gives the same indications, and an oscilloscope is the only certain way to sort that out. Normally bad alternators produce fairly steady AC voltage while bad batteries may (but not always) jump around.
The failure as I had it was an intermittent internal connection in the battery. The car started okay most of the time but ran very rich, idled very low and had all sorts of other problems. There was never any code stored because the ripple from the alternator continuously reset the computer. The new battery fixed it right away.
Mike
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Oops - missed the part where you replaced the battery already.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.