I recently bought a 94 Honda Accord, this will be my 5 Accord. It currently has 184k and I have been getting it ready to put it out on the street. When I drove it home the temp needle stayed below the half Mark all the way home on the interstate. As soon as I got off the interstate the needle rose alittle pass the half way point. I did some checking and fans where working with the a/c only on. So I decided to change out the 2 sensors and the 2 thermal switches as well as the t-stat. I did all that and the needle still goes pass the half way point, but goes pass it less than before. Now as the needle passes the half way point the fans kick in the drops to the half way point. Figuring something is still wrong I bring out the temp gun. At the water out let housing and t-stat housing the temp never went pass 195. The fans kick in at around 195-196 temp on the t-stat housing. Now I know that Hondas are very excellent cars so this fluctuation of the needle is wording me a bit as I don't recall ever seen any of my Honda temp needles vary this way. All the sensors where from Napa and the t-stat from advance auto, its a stant t-stat. What do you guys think is going on? Can it be the none OEM parts?
Thanks

 

If thermostat was Non-OEM, that may be the issue. When you drive on highway and exit, cooling demand would increase (heat load from highway, reduced rpm, and airflow), so thermostat should open slightly to increase cooling flow. A "lagging" thermostat may allow the temp to increase due to failure to change position (sticky movement).

I've seen this exaggerated in a thermostat that was failing.

good luck

 

Thanks TexasHonda, I will buy a OEM t-stat and go from there.

 

Well if the "temp gun" tells you the temp is 194 then I say life is good. The sending unit (ground) may be getting old and showing a slightly higher reading than most others.....just like my tach (95 EX auto) reads 2,000 rpms while going 65 mph.

 

I had though about that, but when I am on the interstate temp needle is where it should be. I already ordered the t-stat at the dealer and I will just return the auto parts one. Nothing like OEM parts, but I should have know that from the begin. If that doesn't take care of I will look at the sending wire for sure.
Thanks