Re:G13BB Engine runs rough intermittent

Take some water with you. When it does it, pour the water on the cam sensor. If it cures it then you have found the problem

Sent from my Pixel 2 XL using Tapatalk

Thinking cam angle sensor as it has that surging feeling, feels like engine surges forward then stops surging, bit of a stutter, that's probably a more accurate way to describe it. just had head gasket replaced on this one.

Thanks Martin, problem at moment is it comes and goes and each episode is for no longer than 5 secs. Warming up period is usually fine. Then it might go ok but the performance is lacklustre on acceleration , it does accelerate but I think its slower than usual. I will put a bottle of water beside me and try it next time it has a engine wobbler. Thanks for the tip Martin.

Having the Cat converter assessed Tues next week, he said if it is bad, he can fit a 'high flow' cat , price was reasonable.

If it only lasts 5 seconds then I would not think it's the cat blocked. With a blockage of the cat it tends to last as long as "more power" is needed ie. Up an incline.

Sent from my Pixel 2 XL using Tapatalk

It sounds electrical, sensors, coil packs or leads?

Sent from my Pixel 2 XL using Tapatalk

Thanks Martin, will keep at it , given the nature of it , might take a while find it. Not getting a check engine light so cant draw any info from a code which would be handy.