I have a 2005 Scion Xa that has an engine problem for eight months straight. The problem is it won't start. If and when it does and it is put in gear and stalls like the timing was off. The sound it makes has been describe as "Running on one piston." The problem comes and goes, some days it runs fine others it's just dead in the water. The electrical, belt and timing was checked out by three different shops and found it to be working fine. But after it sits idle for more than a day all the same problems return. It's been taken to the Toyota dealership in Warner Robins, Georgia and they couldn't find nor fix the problem. It was taken to two other local mechanic shop and the last one found it to be the on board computer. They located a used one and said it was running fine and ready to go. After the services were paid for and as my daughter pulled out of the parking area it stalls again. Luckily their work was under warrantee. Has anyone gone through this problem with this same make and model?