I have an 07 Saturn Vue with a 2.2-liter engine that has 147000 miles. The engine runs great but every time I place the shifter in Reverse the idle drops and the engine finally stalls. This does not happen in drive or any other available positions. The car idles around 1200 RPM in part and drops to 1000 RPM when placed in drive. When placed in Reverse the idle drops to around 400-500 RPM and the engine stalls. I have replaced the throttle body, ECM, MAP sensor, and temperature sensor but no change. Does anyone have any suggestions?

 

Stop throwing parts at it.

Automatic at idle should be done around 750 RPM for that engine. Your high idle as likely due to a vacuum leak.

From a cold start, with the engine running, spray carb or choke cleaner along the intake manifold fports, he junction between the throttle body and intake manifold. If you here the RPMs increase, you've found your leak.

 

Prior to this post I had spray around the engine thoroughly with carburetor cleaner and did not notice any increase in engine speed

 

What else have you tried?
is the Check engine light on?
If it is, please go to AutoZone or similar to get the codes read for free and post them here in the format Pxxxx where the x are numbers.

Does it struggle and stall?
Does it run for four or five seconds then install?
Do you have traction control, stabilitrak, or other messages on the display?

Two-wheel drive or all-wheel drive??

 

Itit is two-wheel drive. It struggles a little bit because the RPMs are so low. It runs pretty good for about two or three seconds and then the RPM's dropping it begins to stall... No codes... Nothing like traction link etc

 

can you feather the gas to keep it from stalling?

 

No..I have tried that but usually it continues to stall