Question about cruise control servo

[derolph]

The cc in my 88 LX-i works but it has a defect. It does not hold a constant speed, even when driving on a long stretch of perfectly level highway. It will vary in speed by 3 or 4 mph; it will slow down a bit and then speed up and then slow down, and on and on, repeating the cycle every 20 seconds or so.

I'm guessing the servo unit is the culprit. I found a used one online that is for an 87-89 LX. LX-i is not mentioned in the listing. So, I'm wondering whether the same model servo works with both Accords with a carburetor and Accords that are fuel-injected, i.e. LX-i models.

[derolph]

Maybe servo is not the right term. I looked in a Chilton manual where I saw it labeled Actuator. I also read a Cruise Control Diagnostic Chart in the manual. It gives me the impression the problem may be the Cruise Control Unit which, according to the manual, is located under the left side of the instrument panel above the fuse box.

[Dr_Snooz]

What are you referring to as the "servo unit"? Do you mean the vacuum actuator that pulls on the throttle butterfly? I believe those are the same, or at least can be made to work interchangeably.

In all truth, what you are describing is pretty much considered normal operation for these older systems. Mine does the same thing. You can try changing parts, but it probably won't help much. If you are serious about digging into it, you can download the Honda manual and work through the troubleshooting procedures listed on p. 25-71 and following. They will help you find out exactly what part is failing.

[derolph]

What are you referring to as the "servo unit"? Do you mean the vacuum actuator that pulls on the throttle butterfly? I believe those are the same, or at least can be made to work interchangeably.

I see you posted soon after my last post and apparently did not see my last post before you posted. Yes, I mean the actuator.

In all truth, what you are describing is pretty much considered normal operation for these older systems. Mine does the same thing.

Oh, really? Well then, I might just drop the idea of getting it to work right. I'm a frequent user of cruise control in my other car but I can do without it in the LX-i if trying to get it to work is not likely to be successful. It's not worth spending a lot of time and incurring significant cost to pursue an objective where a favorable outcome is very doubtful.