Hello, I drive a skoda fabia and I noticed that when driving the car jerks and when stationary the her king is more especially when the AC is on in the car. What could be responsible for this as it's getting very serious. It only gets a little better when the engine has run for some time. Kindly help. Thank you. 

Welcome.

Best say which Fabia & if a Mk1, 2 or 3.

Maybe worth posting in the section that applies telling a bit more which engine you have.

Thank you for your response. It's a skoda fabia 2008 model Saloon. 

Petrol or diesel? Do you know what size the engine is, and whether it has a turbo?

It's a petrol engine and I think it's 1.4 ltr engine and don't think it has a turbo.

My daughter had a similar thing in a Toyota Yaris, which is an automatic. Stop and apply the handbrake, the revs raise and lower intermittently,  making it feel as if the car wants to drive off. I think it seems to be related to the air-con coming on and off, changing the drain on the load  and making the revs change a little. I am sure the a/c is in need of a re-gass so perhaps this is the place to start looking... Does YOUR car need the air con re-gassing? It might just be trying to work too hard! It helps if she slips the car in to neutral whilst stationary, to alleviate the symptom.

Thanks you but that's not the issue.  My ac gas is okay. The car jerks even when the ac is off and especially when and stationary. At some times the car goes off.

On the plus side the straight 1.4 is a simple engine. Where is it with regard to service schedule? It might just need new spark plugs or leads/coils, or it could be something else like oxygen sensor or manifold pressure sensor. But a good service covering all the basics like spark plugs, air and fuel filters, and of course oil and filter would be a good place to start if not all recently done and running some fuel system cleaner through with your next tank of petrol may also help.

 

After that it will be a case of getting it to someone with diagnostic equipment to look at the sensors etc.