My 1997 sunfire is stalling, running rough as if timing is off, grayish smoke coming out of exhaust, will not accelerate, transmission is winding out really far before changing gears, black smoke, felt like i had a flat tire. Just put a new starter in it last week, new catalytic converter, has 240,000 miles. Was running great 3 days ago. Serviced regularly. Please help we can't pay for an answer. We have hack mechanics trying to help us....my boyfriend is great with cars and started restoring a 66 Nova until he went blind 15 years ago. It is still sitting. I am unemployed and really desperate for some feedback....Thank you!