オリジナル投稿者： BeenThere DoneThat ,
So far as the rough idle goes, (I cant say about the speedo) I'm going to hazard a guess you have a problem with the Idle Air Control Valve or some call it Idle Air Motor. It's generally located on the throttle body and in the case of my 2000 Dodge Ram 5.9l gas engine, it's pretty easy to change and was fairly inexpensive. When I was searching for this on my Dodge, most said it was a good chance that it could just be removed and cleaned and replaced. At least in my case, that did not fix the problem. I had to purchase a new one. Search Google for "1999 Camry le Idle Air Control Valve" and see if others descriptions of their problems don't sound like yours. Good luck my friend.