We have a Chevy Impala with 2 codes constantly coming up. One is P0700 (Trans Control Sys Malfunction). We were told that one is because the gas cap is not on securely. We turn it much more than 3 times, after gettiing gas, so we know it IS on securely. The other code is P0742 (Torque Converter Circuit Stuck On). The car sometimes makes a loud noise when trying to brake, then bucks like crazy. This doesn't happen all the time. HELP!
Make : Chevrolet
Year (other): 2006
Make (other): Impala
Putting in cleaner before filling to clean the emissions system. We did this twice.
HI my name is XXXXX XXX I will be happy to assist you today...
ok first off the p0700 has nothing to do with the gas cap. Your TCM (transmission control module) does not have the ability to turn your check engine light on. It sends information to your ECM (engine control module) this code is generated to tell your ECM that there is a transmission problem that is emissions related and to turn on the check engine light
Now...the P0742 indicates there is a fault with the TCC solenoid (torque converter clutch). With the problems you are experiencing you most likely have a bad TCC solenoid and it will need to be replaced. this is inside the transmission and should be replaced by an experienced auto repair facility.
I have been repairing cars for 20 years.