Common mods for the TD5 are

EGR Blank
De-Cat
Straight Thru (does make it a tad louder)
Remap

Done all that to mine and Ive got loads of power when I need it, loads of torque, sits better (and quieter) at motorway speeds and consistently returns 28 - 30mpg. Though I will be fitting a larger intercooler as well, get the best out of the above mods.

Just got to keep an eye on the MAF and MAP sensors, can get dirty and cause minor issues.

In the 3 years I've had my TD5 I've only had one electrical problem and that was down to a bad battery earth so could happen to almost any car.

EGR blank was going to be my first mod. Can you tell the difference even on the autos?
MAP and MAF sensors. Don't even know what they are let alone where they are. Lol. Will have to get mulling over the workshop manual.

MAF - Mass Air Flow sensor sits in front of the airbox before the turbo. Basically governs fueling based off air flow. If uts dead only ever replace with genuine LR, Seimens/VDO.

Youll know if its dead as the first 10 seconds after start up it will have almost no power even full throttle, the suddenly all the power kicks in.

MAP - Manifold Absolute Pressure. Sits in the middle of the inlet manifold on the left of the engine.

Unlikley to fail but does get dirty especially if the EGR is still fitted. Takes 5 seconds to clean with a clean cloth and some brake cleaner.

Does make a difference blanking the EGR maybe not totally noticable but youll get a tiny increase in power, MPG will increase as the engine can 'breath' easier as it doesnt have dirty exhaust gas being forced back into the engine.

Thanks for the info mate. Very helpful. Having changed my filters today, I'm surprised any air was getting past the air filter, let alone needing to blank off the EGR. Lol. Shocking state. If only people did the basics. So much better for longevity

Very much so!

I decided I would just go for the EGR blanking plate rather than the whole kit. Only the one gasket though it would seem. Oh god. I am starting to mod before it is properly sorted. Lol