[ErikGG]

I have a 2004 cooper s and when I put in reverse it shuts off, I can drive in all gears. Why? Why?

 

[Rockster]

Is the check engine light on?

If so getting the associated error codes is a start. (Uh, no pun...)

Could be a number of things. Someone is going to have to get his hands dirty to diagnose this and I would hazard a guess is it a pretty involved diagnosis. There's fuel, spark, transmission fluid level and condition, possibly a bad/loose crankshaft position sensor and if a key is needed to start the engine a bad ignition switch.

 

[ErikGG]

Thanks, its just strange that it starts fine i can put in 1-6 gear fine, but just reverse is when it shuts off, no sputtering nothing. As if the reverse is acting like a off switch.

 

[Rockster]

Thanks, its just strange that it starts fine i can put in 1-6 gear fine, but just reverse is when it shuts off, no sputtering nothing. As if the reverse is acting like a off switch.

Agree it is strange. I can tell you I had a M-B cargo van that the engine would shortly after a warm start die like I flipped an off switch. This dying coincided with me shifting -- sometimes -- into reverse. The problem was traced to a bad low pressure fuel pump. But the tech eliminated other possible causes. And to confirm the fuel pump was bad he had to drop the fuel tank. The low pressure fuel pump was replaced and the behavior went away.

For a while.

Then the engine died shortly after a cold start and died with more drama. And the restart was not clean either. This really felt like a fuel supply problem and that proved to be the case. The tech found the replacement fuel pump was bad.

 

[Tommy.org]

Maybe it's too old. Did it turn on any trouble lights?