Hi own a 2001 ford focus not sure of milage on it,,last week when at a red light,car felt like it wanted to stall,happened about 3 times in a couple of days,,took to a garage,put it on a diagnostic computer,,( wasnt sounding rough when i went) they found nothing no codes came up ,nothing checked fluid stopped up oil but did say transmission fluid was dirty,, and said to bring back if it was acting up again ,,early wed morning ,leaving work i started my car,i had to jump out the smell of fumes and something else i cant pinpoint and it was bogging,,my next stop upon leaving i stood outside and could smell this same odor more so coming from under hood looked the smell was there,,,,,took it back to garage,,,they put on a hoist and had it running for 15 mins the car had already warmed up as it was later in afternoon when i got there,,3 mechanics were under sniffing and came up with nothing ,,leaving my friends house after shopping car had been sitting for 3-4 hours,it sounds so rough,, its getting worse,,would dirty transmission fluid make my car behave like this?