Just a query; about installing an air inter-cooler

I would install an external trans cooler. You figure that plow makes a nice air block for fresh air getting to the cooling pack. You have an AC condenser, probably a power steering cooler, trans cooler, radiator, and if it is a turbo diesel there will be an intercooler for the air to make it thru. If the truck already has a separate trans cooler that is not integrated into the radiator, I would think an electric pusher cooling fan might be the ticket.

code p 0299 refers to turbo/supercharger ---low boost=== causes --- mechanical fault
check for all turbo hoses tight , inter cooler not split or has a hole in it

Check that the intercooler is in good condition (no cracks or leaks) and the hoses are tight at the hose clamps . Next talk to a diesel pump repair specialist as you may have to re-tip the injectors and re-calibrate the pump for the extra air that the turbo produces. Check that you have the correct turbo for the diesel

Replace battery

the liklihood isnt hi, most tdci engines are very reliable, as for the intercooler packing up i dont see that happening with normal use, blow by would be the only thing that would really worry you but a car this young wouldnt have issues. i think that you would be happy with the car and if you keep the services up like the previous owner the car will show you no problems :)

if you do by pass it i would leave the turbo in operation and just remove the hose of the inter cooler and put a air filter in place of the inter cooler.

Try this link -- http://www.auto-repair-manuals.com/1990-2007-Toyota-Landcruiser-Diesel-Engine-including-Turbo-Auto-Repair-Manual.html

U have a serious turbo seal failure problem.

it sounds like your turbo has packed in firstly the oil seal in your turbo has failed thats why ur seeing oil from exhaust & the whistling from turbo is the vanes in turbo breaking up so i would advise not to use car until new turbo is fitted & inter cooler pipes and inter cooler itself are checked & cleaned for swarf from turbo you can check turbo by disconnecting turbo pipe &inspecting turbo vanes (fins) to see if broken up or any damage to chamber.

Can you hear the turbo spooling up? If yes do you hear an air noise... could a number of things from bad turbo, air to air leaking or its piping, or something simple like a clogged fuel or air filter.