S320CDI 4 years old auto box becomes non responsive wont change down and power is lost like the turbo has shut down, No fault code and resets on switching engine off. No obvious driving pattern causes this

You need to have a Powertrain control module fault code test run, this test is key to understanding what may be causing this, this engine is 100% computer controlled.

Hi Did you by any chance have ignition swithed on when you refitted new battery? If so disconnect negative terminal at battery for about 5 minutes all modules will go to sleep and reset (ign off) reconnect battery and try again. If that does not work you will need a fault code reader. It is advisable to connect a fault code reader 1st however as you have already disconnected the battery it has probabley lost any fault codes anyway,Good luck

Check power and ground cables first.

run fault codes and look for TCM and other electronic problems in the transmission.

IT IS GOING INTO LIMP MODE. COULD BE A TRANSMISSION ERROR. THE LIMP MODE IS DESIGNED TO PROTECT TRANS AND ENGINE FROM FURTHER DAMAGE

code p1105 refers to manifold absolute pressure(MAP) sensor, TC system-leak detected. causes ---intake leak, ---hoses There are to references to p1105 The second response is still map sensor but the causes are---TC system--mechanical fault--air leak between throttle body-TC,map sensor---TC system--exhaust blockage
code p1260 refers to throttle return spring--weak spring force. causes ---mechanical fault,--,throttle control unit
code p1264 refers to throttle valve opening-accelerator released causes ---throttle control unit---mechanical fault

Hi,
you need to get the codes read first this should give you fault codes if no codes check the vacumn pipes for splits etc and read the live data for the mass air flow sensor,it will either be an over boost problem or low reading MAF sensor causing the turbo to shut down all you do by ignition off and then on is reset untill it see`s the fault again.

Take it back to the Dealer........Their Problem not yours.
It is possible that a plug was removed during the service and at some stage the ignition was switched on before the plug was reconnected , this would cause a check light and the computer would store this until the light was reset.
Hope this helps.

In year /model 87, code 23 was oxygen sensor stuck in full rich position. I'd be tempted to try a new one.

Hi,
The first place I would look is the shift linkage for wear and a sloppy connection from wear.
adjustments may be made as a possible fix on the linkage rod.
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