I have a 1992 Honda Accord LX with 119,000 miles. Lately i have been losing coolant and can not find a leak. She has just started running a little rough and feels like she might stall. Usually runs great. Hoping someone can help.

 

Just saw this post. I'd say rent a radiator pressure tester. When the engine is cold, remove the radiator cap, top off the coolant, then put about 15 psi with the hand pump. Then you can try to find the leak.

Sometimes the leak isn't obvious when the engine is hot, because the water in the coolant will vaporize.

 

+1 on the pressure tester. I was losing coolant but didn't notice a leak even after replacing the rad cap (some had mentioned that that could have been the issue). After using the pressure tester, I saw that there was a crack on one of the hoses that I wouldn't have been able to see otherwise (leak was facing toward the engine bay).

 

you stated :She has just started running a little rough and feels like she might stall. Usually runs great.
Just a coolant leak assuming you have enough coolant left in engine will not effect how well engine runs, unless you were totally out of coolant and possibly overheated the engine
hopefully for you it is not the latest , if it continues to run rough you might want to do a cylinder leak test make sure head gasket is not damaged and chk for white smoke coming out of tail pipe