Problems with 2007 Mazda CX-7 POWER TRAIN

I have a 2007 mazda cx-7. it is a very beautiful car but also has tons of problems. at 15000 miles it was leaking oil and they replace the engine gaskets. then later was also leaking oil. was told by the dealer that it was not. took it to someone else who said it was leaking from the timing chain. mazda resealed it. since then my car doesn't shift properly going up and down hills. my air conditioner is hot and makes a funny sound. my car has loss of power and sound like a diesel. overall i think that mazda needs to step up and take care of the problems or they will not get many returning customers! something needs to be done! it was a 35000 dollar car! *tr

I purchased a brand new 2007 mazda cx-7 in april 2007, the vehicle started experiencing engine problems in september 2007, i was told it may have something to do with the vvt (variable valve timing) and timing chain. the vvt was replaced by the dealership a short time later; however, not the timing chain. after the vvt was replaced my vehicle starting to experience thick white smoke coming out of the tail pipes. my dealership technician advised this was due to a turbo issue with the engine. all of this occurred within the first couple years of my ownership. i have had the turbo repaired (out of pocket expense), as well as the vvt (2 times) and the timing chain it all seems to no avail. the car is revving very high on cold start ups and is now experiencing a code as of the last couple of days that is stating there is a decarbonization issue with the engine that is linked to the timing chain. of course this is now the 5th time this vehicle engine will be opened up to diagnose one of the known issues that mazda north america is aware of. i have had this vehicle since 2007, and has just over 120,000 miles on it. i have maintained a very good service history on the vehicle taking it to "reliable" mazda dealerships in the area where i live. my main concern is mazda is doing nothing to rectify the issue and it's only a matter of time before someone is seriously hurt or even worse. the vehicle safety is impaired due to unstable engine performance. there is obvious technical issues with the engines for this mazda engine model. *tr

Dt*: the contact stated upon acceleration, the vehicle hesitated. it was driven to the dealer who determined the control module computer in the power train needed to be reprogrammed. the vehicle was a 2007 mazda cx-7. *ak updated 10/31/2006 - right front window failed. the dealer replaced the left front switch. *nm