For some reason, my car bucks and struggles between 40 and 50 mph. The car runs smoothly between 0-39 and 51-max speed. It is only between 40-50 mph, that the car shakes and feels liek it is struggling to accelerate. I took it to the dealership, and they told me something about reprogramming speed calibration. Even after that was done, the car still does the same thing. Has anyone has epxperiences similar to this?

For some reason, my car bucks and struggles between 40 and 50 mph. The car runs smoothly between 0-39 and 51-max speed. It is only between 40-50 mph, that the car shakes and feels liek it is struggling to accelerate. I took it to the dealership, and they told me something about reprogramming speed calibration. Even after that was done, the car still does the same thing. Has anyone has epxperiences similar to this?

That could be the point where your torque converter is locking putting a little more strain on your engine. It is very likely a coil problem. Do a search on that. Most of us have run into the same thing and you will see many suggestions and a tech article on the fix.

Good luck!

If you have the V8 lsbit did a great write up on how to replace the coils/ valve cover gasket. Chnaces are if you have a bad coil and you own a V8 the gasket is leaking.

maybe I don't understand - how is a jerkiness in a narrow speed range related to coils?

could be under a load at that point. I notice misfires at particular loads and speeds.

When I had the VC leak, and coils were blowing like crazy, the car drove rough around 40-50.

could be under a load at that point. I notice misfires at particular loads and speeds.

Yep. Most people drive their car in D5 and 40-50 is where it just bogs down due to converter lock-up. After you get past that, the load is not as bad. That's what I've experienced anyway.

For some reason, my car bucks and struggles between 40 and 50 mph. The car runs smoothly between 0-39 and 51-max speed. It is only between 40-50 mph, that the car shakes and feels liek it is struggling to accelerate. I took it to the dealership, and they told me something about reprogramming speed calibration. Even after that was done, the car still does the same thing. Has anyone has epxperiences similar to this?



hey my car does the same thing its werid. i cant find out why it does it. i been everywhere.

hey my car does the same thing its werid. i cant find out why it does it. i been everywhere.

Check if the car has a rough idle at a stoplight, because my car struggled around 40-50 (shift into 5th) at about 1500-2000 rpm. Anymore rpm's than that and it was fine. It was due to a valve cover leak causing coils to blow.

-wrong thread

Im having the same problem, I just started noticeing it this weekend. Does enyone have an estimate on how mush it should cost to get fixed? Right now Im not throwing the check engine light, but I have exsperienced the hestitation under load \ misfireing in a narrow rpm range in D4 and D5.