hesitation on acceleration

Post here for mechanical and engine topics such as fuel issues, transmission problems, rough idle, exhaust, electrical issues, etc

Moderators: GRNSHRK, ron, bfons

Post Reply
User avatar
slofut
Posts: 778
Joined: Thu May 30, 2013 1:29 am
Location: SW Ga

hesitation on acceleration

Post by slofut »

Both my 635's (87 and 88) do this for some reason and I've never dug into it other than checking for vacuum leaks, but I thought I'd pose the question here for some thoughts.
The best way to describe it is the same symptom a carbed car would exhibit if it had a bad accelerator pump. From decelerating at speed and on over-run ...punch the throttle and you want to fall over towards the steering wheel for a second before you get acceleration. You can also get the same hesitation at idle in neutral when revving the motor, and with the auto box when you floor it and it downshifts to pass another car. It's certainly annoying although I've lived with it on both cars for years, and the car runs fine otherwise except for the obligatory rough idle.

Any thoughts would be appreciated
'87 635csi, 5sp man, dk blu on pearl beige
'88 635csi, auto, black on grey
'63 BMW Isetta
'75 XJ6C, 2dr, warm 350
'86 XJ6, th700r4
'75TR6
'64 Olds 88 conv
"68 T120 Bonneville
Post Reply