RD28 & RD28ETi

Hi guys, this might be a stupid question but I am a bit confused in the differances between the RD28 engine and the RD28ETi....Is there a difference? If so what is it?
My 98 GU has RD28 on the complience plate and is a 6 cylinder intercooled turbo diesel.
Any light you could shed would be appreciated.

Thanks, Mark.

Mark
I might be wrong but i think the 98 GU has the RD28 ETI engine, my GU also has RD28 on the plate, i think the RD28 was a mechanical pump motor in the GQ

Yeah thanks Shoot, just went through the id numbers from the plate in the manual I downloaded from here...and yes I would say you are right even the plate says RD28 the numbers match the RD28ETi motor.

Thanks again..

Downloaded the manual this morning, good stuff
Shoot

Sorry to revive an old thread.
I've got a 96 GQ with a 2.8, how can I find out which it is?
Thanks!