I noticed a wile a go my car reving and going into fail safe mode then I went to my mechanic and he noted that my engine head seals and transmission seals need to be replaced so I did and also changed the transmission oil, after that my car ran normally for three days then I noticed that the car stats to shake wile in Traffic exactly like it you have a bad ignition coil but it comes and goes although I changed them recently and new spark plugs so it doesn't make since that it went wrong less than a month of changing them I'm really puzzled by this and I'm thinking it might be a bad throttle position sensor
My car has 174000 miles.
My car has an automatic transmission.
Hello, thanks for writing in. For an issue like this we usually need to start by scanning the computer for codes. This will allow the mechanic to see if the computer is seeing any problems. If there are no codes then we would need to drive the vehicle for a while with a scan tool installed to monitor the engine sensors to see where the problem is. It sounds like a timing chain issue or an airflow sensor that may be failing. For this service, consider a YourMechanic certified mechanic to come to your home or office to diagnose and repair the shaking issue. Alternately, if you know what fix needs to be made, you can have a timing chain replacement or mass airflow sensor replacement.