The car runs without a battery, not the same as a bad one. I had my battery disconnected, and then brought the car in for emissions testing and the sensors where not online, it took 598 miles till the scan tool showed everything to be emissions compliant. During this time the afr was runing rich from idle on up, it started getting better but didn't reset the emissions sensors till we went 598 miles. I originally thought the tune was wrong but after speaking to Jerry at LET he had the same problem with his C32. Easy to confirm. Disconnect your battery for a few minutes then reconnect now use a simple scan tool to check the engine status it will tell you what emission sensors are off line, same ones which I listed in another post, 3 of them. You will be driving around for a while till they come back on.