Let me start by saying I'm new to these forums and new to Honda. Last night, I drove home what I believe was a sweetheart deal on a 91 Accord SE, though I won't bore you with details (unless requested). Long story short, I have a quick question on some possible maintenance and vehicle behavior.

Driving home at about 60mph on the highway, I noticed that the RPMs hung around 2800 to 3000 (in D4). I know that Hondas typically rev higher, but besides that, I'm not really familiar with how they behave on the highway.

The other thing I noticed is that for the 40 or so miles that I drove, it didn't get terribly warm. The temperature gauge showed that the needle moved to about 1/8th above the Cold hash mark, possibly between 1/8th and 1/4 overall. The heater gave great heat, but I was concerned the engine wasn't warming up correctly. Because I was getting the correct amount of heat in the cabin, I'm inclined to think it's the coolant temperature sending unit, not the thermostat.

Finally, it would appear that the shifts are not quite as harsh when in Sport mode. I'm not really sure if that means it's better for the clutch packs in terms of longevity, but when I had a Jeep Cherokee, Power mode was what everyone used for both of those reasons.

Can anyone offer their $0.02? Thanks!

 

I have had non Honda's have similar heat symptoms when a thermostat was removed to 'fix' a over heating problem. At highway speeds the coolant is cooled below the range the normal operating range when the t stat would normally close. At 105 degrees and 190 degrees the heater core will still warm the cabin sufficiently. But not reach 'normal' operating temps. No harm if the t stat is missing, although it will effect idle.

On the rev's, did it not ever go over 3k or that is just where the engine was happy in that gear? If the engine won't go above this, the ECU might be in limp mode due to bad a bad sensor(s). How is the power and response? Does it pull up through the rpm's steady and smooth? It may just be where the engine is happy in that gear. Try others and see if the range changes.

 

Thanks for the response, TejasNW. I was considering changing the coolant on her anyway - maybe I'll just replace the thermostat while I'm at it! The idle holds okay and the A/C doesn't seem to kill the car, though the RPMs can be somewhat erratic, it doesn't die on me.

I was pretty sure I was doing the right thing by using D4, but I didn't want to go too fast on the highway til I got home and read the owner's manual. I probably went between 58 and 62mph the whole way home and it'd be between 2800 and 3050 RPMs accordingly. The car didn't seem to be having any trouble and was driving well (I assume Honda 4 cylinders are a bit noisy on the highway as a result.) Power delivery on the highway and city seemed fine as far as I could tell, though once a downshift did cause a rather large spike in RPMs.

 

One other quick question - what automatic transmission fluid should I use? It sounds like some folks are claiming to only use ATFII and some say only use genuine Honda ATF, but I read there may be some compatibility problems.

 

I am no expert on the ATF question. I have always heard that it must be Honda ATF or problems would develop. If others have used ATFII with success, I am not aware.

My recommendation is to go with is know to work. Peace of mind is worth it, if nothing else.