HI I Have a 940 2ltr turbo Wentworth estate having done 110.000. the problem I have is frustrating.
I recently had the head done and ever since I have no turbo. I did not realise until the day after I got the car back that it was not working I have had it back to the garage who is a small independant but volvo trained. he cant find any fault but it does not kick in.(I have used this garage for over twenty years with no problems before) The car runs perfectly well without the turbo but lacks that extra punch when overtaking etc. I have also taken it to another volvo garage near to me and they say they cant find any reason except it's not working. (it was working perfectly before the work).
so it looks like I have to find a replacement unless any one out there can think of a reason. Hopefully Rob

Hi, I use to have the 940 2 ltr. Wentworth saloon but it was 1991 the engine layout will be the same. It was a mitsubishi turbo, which is the one that spools up pretty quick, yours should be identical. The first place you should start is to see if the wastegate rod, which as you look at your turbo is underneath it, is attached to the wastegate lever,a clevis pin keeps the rod in place. Sometimes this pin rusts and falls off then the rod will come away or the whole assembly with wastegate lever can seize with rust.Just make sure the rods connected and the assemby is free to move left to right if it doesn`t loosen it up with some penetrating oil.You may be able to see this proper from underneath the car or use a mirror under the turbo.If this is all OK you can then go on to check all the hoses which supply the compressed air to the intercooler and on to the throttle assemby.They of course must have no holes and be secured properly with tightened jubilee clips.There is a metal cover on the side of the turbo ,which you can see full on, which is held by three bolts, make sure these are tight as there is a blow off valve underneath it which may leak and let your pressure go, you could dismantle this and clean it and make sure it is not torn or damaged. Just make sure the other vacuum tube is connected to the block by the throttle plate and is clear. Check that the actual turbo wheel with the fins on is free to move inside the turbo,you can see this with the top hose removed. Regards