cold start on reverse stops not not forward

[mrfochon]

have a weird issue when starting and reversing within few seconds, the engine will stop; but not if going forward.

any ideas?

thank you

[suitedcboy]

The ratio differences 1st and R affects how much throttle it takes to move car and that affects the transition back to idle. I would clean the throttle before doing anything else. When that crud layer is thick enough the throttle can overtravel and stick in it for an instant and stall engine. Don't use anything aggressive s there is risk of solvents leaking down throttle shaft and into the position sensor. WD-40 or other penetrating sprays on a paper towel or cloth rag will usually cut and clean it off. Key off first then hold the throttle open with a finger while wiping the bore clean and then the edges of throttle blade.