While accelerating from 35 to 40 and from 45 to 50 i feel a jerky motion during acceleration. What could this be? we are taking it to the shop on friday just want to know the problem before they tell me

You must be aware of all the feasible reasons behind the problem in accelerating before jumping to the solution. The car jerking problem happens to be an issue common in both manual and automatic cars

SERVICE STABILITY SYS
Refer to ABS Description and Operation in Antilock Brake System ! You need to take it an have DTC'S diagnostic trouble codes read ! That will point you to a diagnostic path !
Vehicle Stability Enhancement System (VSES)
The vehicle stability enhancement system (VSES) adds an additional level of vehicle control to the electronic brake control module (EBCM).
Yaw rate is the rate of rotation about the vehicle's vertical axis. The VSES is activated when the EBCM determines that the desired yaw rate does not match the actual yaw rate as measured by the yaw rate sensor.
The desired yaw rate is calculated from the following parameters:
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The position of the steering wheel

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The speed of the vehicle

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The lateral, or sideways acceleration of the vehicle

The difference between the desired yaw rate and the actual yaw rate is the yaw rate error, which is a measurement of oversteer or understeer. If the yaw rate error becomes too large, the EBCM attempts to correct the vehicle's yaw motion by applying differential braking to the appropriate wheel. The amount of differential braking applied to the left or right front wheel is based on both the yaw rate error and side slip rate error.
The VSES activations generally occur during aggressive driving, in turns or on bumpy roads without much use of the accelerator pedal. When braking during VSES activation, the pedal pulsations feel different than the ABS pedal pulsations. The brake pedal pulsates at a higher frequency during VSES activation.
If you do not know about this , I suggest you take it to a ASE certified repair shop that does !

It can be a few things wrong here so the best thing for you and the safest for me to say is take it for a m.o.t even if you still have a long m.o.t. left not much money to pay to get this right

i would take it to a muffler shop they can pressure test your exhaust system to see if there is a leak in you exhaust system

If it only happens in one particular speed/RPM then I would be looking into TPS throttle position sensor. Please check and spray carb cleaner on the MAF mass air flow sensor only.

If the smoke is blue, it is burning oil. If it is black or dark grey it is running way too rich, like your choke is stuck on. That would also explaing the jerky acceleration and poor response. Your fuel consumption will also skyrocket.

Go to autozone they have a free OBD 2 code reader. Start by finding out what that code is. It might be something as simple as an O2 sensor. Hope this helps.

Yes it does. But I would clean the throttle body first by taking off the hose that comes from the air filter to the throttle body, held on by a steel clamp. Hold open the throttle plate and spray it down with a brand name carb and choke cleaner. Keep me posted please.

Well for one, make sure you speed up slowly, dont HIT the accelerator. It may also be problems with your fuel filter. After you are stoped fuel stops running through the fuel pump/filter and then when you start going its starts to run through again and it cant keep up so it gets bubbles in it and doesnt move throught the filter easily hence the jerky accelerating. Good Luck

Slipping clutch.