Today I took off boost sensor and EGR valve to clean them, as I've noticed a bit of hesitation about 1.8-2k revs sometimes. I am running a tuning box, but this hasn't caused any probs in about 15k of running. I've taken off EGR valve 10k ago so it wasn't too bad... but the main problem I noticed was that where the EGR connects to the manifold, it was all coked up there on the manifold side, almost completely blocked - this is after I cleaned it last time. So this time I had a good poke about with a small screwdriver and sprayed some carb cleaner in there too. Loads of crud came out - and I mean loads.
Then when I took off the boost valve I noticed this was completely enclosed in crap. So sat that in a cap of carb cleaner for an hour, then sprayed it directly with the carb cleaner and it started to look like a boost valve after a while lol!
Popped the lot back together and she started first time - thankfully - was a little worried about my excessive use of carb clearner lol! Anyway, noticed immediately that the throttle response had improved - this is very apparent. Then took it out for a blast and everything felt spot on. Pulls a bit harder again but power delivery seems smoother and the idle is spot on. I know people can clean car parts and then the placebo effect kicks in - but this was a definite improvement. No hesitation now at 2k either.
I'm wondering how safe it would be to spray loads of carb cleaner into the manifold where the EGR joins... I know there is a ton of crap in there. Anyone done this without any probs?