I have blocked off the egr valve on my diesel pick up. Will this make any difference to cold starting?

No. The egr valve normally only operates when engine is up to working temperature

Hth.

yes if it was stuck open in the first place. no if not basically

EGR is only a shameful excuse from car manufacturers for the low fuel burning, high polluting, high consumption engines we're given to drive. You have a decrease in performance using it, but then you don't pass MOT. If that hassle is still not enough, think about higher taxes on polluting cars. Cars that we, owners, maintained well, but they pollute because that's how they were built. Not by us, but by them. Still not enough hassle? Then think of all those shelved innovations, or suppressed inventions dealing with drastically reducing emissions and consumption.

Excuse my rant, I had to vent myself. If you need proof, please read this: https://rapidshare.com/#!download|609p12|3411063765|The%20Elusive%20High%20Mileage%20Carburetor.pdf|13833|0|0