Vectra engine shudder

[Dog_Book]

Or more available torque at useful points in the Rev range

[paula9568]

and a good excuse to fit 314 brakes to the other half

[nickisland]

OK, sorry to report that my engine judder/shudder is back at about 1500rpm! I have taken off the anti shudder valve (that some refer to as the Throttle body) cleaned it out and removed oil from the PCB and also checked the contacts that people say crack. They looked good but I did 'reseat' them by heating gently with a soldering iron. I had a partial blank on the EGR but while I was there put on my old full blanking plate. I've had engine judder with both plates.

On shut down I still get the engine shudder and just to check when I removed the big (boost pipe?) and started the engine and revved a bit the butterfly flap didn't wobble or try and close and in fact on shut down it did nothing and stayed open, hence the shut down wobble. I have read here that some people have removed the flap but I'm thinking this anti shudder valve (that some refer to as the Throttle body) isn't the fault of my shudder at 1500rpm

I did invest in a code reader and I got P400 (EGR not surprised) and also P1125. I see there's a used anti shudder valve (that some refer to as the Throttle body) on ebay for £20. Not sure it's worth it.....I mean apart from the shudder at shut down what else is it doing? I have blanked the EGR...

cheers in advance!!!