I have been reading around the site for a couple of months now and am impressed with whats happening.
I have a little problem myself to be honest. About 6 months ago I purchased an Astra GSi and everything is great, however after a few months I noticed the idling
was a bit wonky sometimes. When I was idling it would sometimes drop to around 200rpm and my engine lights would come on. So I stuck it into vauxhall to get it checked out.
They said it was an easy fix and just had it marked down as a field remedy(Think it had something to do with boost pressure adjustment)
This problem has not re-occured but they said that they checked out the whole car and said I had a leaking exhaust manifold gasket and that I would be losing power from this. When I picked it up from vauxhall and was driving it home, I was able to feel the second boost kicking in (or what felt like it) at around 4000rpm.
Also if i keep my foot on the accelerator at around 3500-4000RPM then it feels like its miss firing or losing gaining power rapidly or jerking. Hard to describe. I thought this could have been the exhaust manifold.
This was a month or so ago. Just got the manifold gasket repaired the other day and the misfiring and feeling of the second boost arent as bad now but still there.
Do you think it is possible that it could be another leak elsewhere? My local garage think it could be a spark plug breaking down at roughly the same load but im not sure.
Anyone had similar problems to my issue.
To my knowledge the only mod's are a bailey dump value and stainless exhaust from CAT back.
Sorry for the long post!