I have an 89 honda accord lxi 4dr. sedan. automatic. nothin done to it. and i have this problem that orrurs every cold season... (ie. late fall winter early spring). My car when it idles during this cold season....is at 1k rpms. normal is around 750 rpms. (line below the 1). as a result of this, the whole shifting is different, 40mps the rpms are at 3k instead of 2k at 70mph the rpms are at 4k instead of 3k...i've brought it to my mechanic and he cant find any problems, but also he just so happens to hooks it up to the machine on a "good day". i never have this problem in the warmer weather... anyone out there know what could be causing this weird problem? and how ic could be fixed? or what to get checked out?

 

Has your mechanic checked for vaccuum leaks. I would try that first. I couldn't find my service manual on the 3rd generation accords but I did find a few interesting things you may want to look into. Check this link.
http://www.autoanswers.com/Chat/00000cb3.htm
I have also read that someone said they changed the coolant temp sensor, and one person changed the frequency valve selonoid (I've never heard of this). Other possiblities would be the fast idle valve (round thing behind the Throttlebody). Try to clean it with TB cleaner.
Check these links for more possibilities and info...
http://3geez.com/showthread.php?s=&threadid=6617
http://3geez.com/showthread.php?s=12...ight=high+idle
http://3geez.com/showthread.php?s=12...ight=high+idle
http://3geez.com/showthread.php?s=12...ight=high+idle
Damn, I just realized that your car is fuel injected. Forget the carb info. It could be the fast idle valve or a vaccuum leak most likely. Post this question on http://3geez.com/ . This board is geared more toward 3rd generation Accords. In this forum there are very few 3rd gens. Most here are 4th,5th,6th,and even a couple 7th generation accords.


Here is a downloadable shop manual for your car http://www.pauldesign.ru/honda/shopmanual.html
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