Motor "hunts" when climbing hill

Newbie alert! whoop! whoop!

I have a '93 Accord EX, 145k. When climbing a hill (not much of one - we're talking Florida here!) the revs hunt about 500rpm up or down every 30 seconds or so --- sort-of like a mini downshift/upshift. No other change - speed stays the same, no lurch etc.

I find this happens with cruise on, and I haven't tried it with cruise off (it's be harder to tell anyway - my foot isn't that steady - I'm not called AccordCodger for nothing!)

Well, i am assuming 3 things
1) you have an automatic
2) this only happened on 1 hill, maybe multiple times
3) you always have the cruis control set at the same speed when going up this hill.

My guess is just what you said, shifting back and forth between 2 gears. It's probably the slant of that hill, paired with the speed your cc is set at.

For example, lets say you set your cc at 30mph. You are cruising around in 3rd gear until you reach this hill. When you do, your car realizes it needs to downshift to keep a steady speed, so it drops to 2nd. Now if this hill were seriously steep, it would have to really give itself some gas hence raise the rpms drastically in 2nd. But you said it yourself...the hill isn't that steep. So it drops to 2nd, but only needs just a bit more juice in 2nd, so your rpms go up only 500. Then as you gain speed/momentum in 2nd, the cruise control tries to keep you going a steady 30mph, so it shifts up to 3rd, rpms drop 500. This may happen a few times throughout the duration of this hill.

Try a few things if you think this isn't the case. Try it on different steeper hills, or different speeds. Try it without cruise control on. Automatics shift automatically, so even with cc off, it will shift, but then you will notice your speed and rpms will go up, therefore you will compensate by giving it less gas to keep the same speed. Essentially doing the same thing the cc does, but this time the car will do those minishifts as you increase or decrease pressure on the gas pedal.
So IMHO, its probably not doing anything wrong at all.

Screw all that, get a stick.

Why you think all [good] race cars are manuals? So they don't experience what you are!

Enough said!

Thanks, Igor.
1. - yes, sorry, forgot to include that
2. - no it's any hill (but there aren't many of them around here)
3. - true - 60 mph

The "hill" on which I first detected this is the Sunshine Skyway bridge! I couldn't experiment this morning - ever-slowing trucks in front of me. Steeper hills are not an option, though different speeds and non-cruise are, of coruse.

But I'm not at all sure about the downshifting theory. I tried downshifting manually from 4th to 3rd (with cruise on), and it behaves the way it should, but the difference in revs is about 1000, not 500. I understand the implications (including the assumption that the torque converter might be slipping in 4th, thus raising the revs and hence narrowing the difference) but that doesn't seem to be enough to explain the narrow change in revs I'm experiencing.

It'd be nice if I knew which gear I was actually in at the time (no doubt Honda has some sort of device to plug in to monitor that sort of thing!)

Passing comment to Schmitey - understood. And I don't think a race car driver would have much use for cruise control either. But having lurked at this forum for a while, I had the impression that some people were only trying to get to and from work like me :-)