Ah cheers mines is the Y17DT in that case chiefThe 1.7 diesel used in Corsa C and similar are all Isuzu units, but there are differences. You're not the only one; I have spoken (and sometimes driven) to breakers and found that they didn't know what engine they had. Briefly:
Y17DTL = 1.7Di = 1.7 Isuzu 16v with turbo but no intercooler, 65hp
Y17DT = 1.7DTi = as above, but intercooler giving 75hp
Z17DTL = common-rail version, 80hp but (afaik) used in Astravan and not Corsa C, Combo, Meriva B
Z17DTH = 1.7CDTi = as above, but 100hp (I think the difference is a variable vane turbo)
In the UK, the badge on the tailgate is usually reliable so I assume you have the y17dt. Entering your reg plate into Autotrader's car valuation or Honest John's VED Checker should also tell you what you have.
i joined mate and that was spot on thanks again,Same as mine, then (I have the Di/DTL but I literally just fitted an IC and instant DTi). Unfortunately, I am in Spain and my car is in UK but scroll up and you'll see a link I put up from VxON (vauxhall owner's network) where pics have been posted highlighting where the switch is. When I clicked on the pics (just thumbnails) it told me I'd have to login/register. It's worth you doing that to have access to those pics and I dare say that VxON has lots of other interesting bits, too. I just stick to CCUK because nobody's banned me, despite posting waffle and usually bad advice - don't want to push my luck with more forums - but more the merrier in your case.