Hi, my son has a 09 Skoda ROOMSTER S HTP with an intermittent engine fault. it starts normally, but occasionally the engine management light will come on and the whole engine will vibrate. If he pulls over and leaves it for 30 minutes or so, it starts again normally and he can continue to drive. We have changed the plugs the coils the fuel filter and the air filter.

@Dom1970 What are the fault code(s)?

I don’t have a code reader and he’s away at university unfortunately 

Do a compression test.

Thanks. Sorry what would this show ?

Always best to do the test before worrying about what the results may mean.

 

If one cylinder has lower compression than the others, that may explain why it's misfiring sometimes. 

 

So if it says one cylinder has low compression what does that mean in terms of fixing it. 

Are you saying that is what the test has shown?

 

Generally on a 1.2 HTP, replacement of all exhaust valves.

Big, expensive job unfortunately. 

Not had it done yet. 

Just got this plugged into a diagnostic and not showing any errors.