2009 Mazda 3 Trans Limp Mode
Hi, I have a 2009 Mazda 3 i Touring with 4 speed automatic transmission. It is a high mileage car as it just rolled over 200k. My problem started in January and would happen infrequently and progressively got worse. When the engine is cold meaning not ran for about 3 or 4 hours (I am in FL where ambient temps are not that cold) and I start it. When I put the gear selector to drive the gear number indicator on dashboard will go from 1 to 2 and then back to 1. If the gear indicator stays in 2 for too long the car makes a thump sound and goes into limp mode with AT light coming on. I then can turn off the engine, start it right back up again and everything is fine, this time when you put it in Drive it goes right to 1 and stays there and drives fine. No CEL lights at all. Mind you when it goes into limp mode the car is stationary with my foot on the brake. If it goes from 1 to 2 and back to 1 quickly everything is fine car operates normally. If you drive the car, turn it off for short period of time around an hour then start it up it will go right into gear 1 and stay there. After it goes into limp mode I scan the engine for codes and I get P0661 - Intake manifold tuning valve control circut low (Bank 1), P0894 - Powertrain, U2064 - Network. I know the P0894 indicates transmission slippage, however the car is not moving and after a re-start everything is fine. The U2064 one I am thinking maybe a loss of communication to PCM by some module? I took the car to mechanic who said my battery was dead, he put new battery in and was unable to get it to duplicate the issue. After driving home from mechanic on first cold start it flashed rather quickly gear 1,2,1 and drove fine. I am not sure why the mechanic who had car for three weeks could not duplicate issue. I have read a lot about the PCM going bad and is able to make car go in Limp mode. I am wondering if swapping out the PCM would be wasting my money? I am probably not going to rebuild the transmission due to age of car and cost. I am trying to decide if I should cut my losses now or continue. Has anyone had a similar experience? I do have a short video I posted on YouTube showing the gear indicator going from 1 to 2 and back to 1, however I am not allowed to post links yet. Any help would be greatly appreciated.