Why won't the aveo shift into overdrive?

Answer 1

I replaced the engine in my 2004 Chevy aveo after the timing belt destroyed my old engine. After I spent 2000$ to replace the engine, the check engine light started to flash (indicating engine missfire), it would not shift into overdrive, and after having the codes read (tranny and missfire codes) my mechanic spent a month trying different things to fix the problem. After doing a ton of research I figured out that anytime you replace an engine in a Chevy aveo, you must take it to a dealership to have a crank shaft variation (or re-learn) procedure done. Now, my mechanic told me he had done the procedure several times and he knew that was not the issue, so before I let him take it to the transmission shop to waste time, I decided to take it to the dealership to have have the procedure done. After 150$ more, the re-learn procedure worked, and I talked my mechanic into splitting the bill with me because we both knew so much time had been and would of been wasted if I wouldnt of figured it out myself. So please, anyone who is having the same problem I promise it's because the procedure must be done once the engine is replaced. It took the dealership several times to get my car to re-learn to shift, but it worked!