That would be the greatest oddity i've ever seen to have good boost but not enough power ... clamp the pipe which goes to te wastegate valve and see if it goes to overboost or not cos if it doesnt means it's not boosting enough at all
I'll try that tomorrow.
You said that before i recommended to tighten the wastegate which you said you did so if it doesnt go above that value means it's low, you can calculate the boost exactly by extracting the AAP from MAP(boost = MAP - AAP knowing that 100Kpa = 1 bar) but usually the AAP is around 100 so you should see MAP around 230 at full load but for that the wastegate must be open which means the boost of the engine is higher(a well fuelled untuned Td5 should peak up to 1.7 bar unrestricted by the ECU)
still low then... try to tighten the rod untill you get 230 MAP but IMO you should replace the wastegate actuator (THIS) and make sure that the turbo's wastegate spigot is not sticking and there is no leak at the exhaust manifold cos it should have been more boost with the rod tightened... in ideal conditions it is rising with around 7-8 Kpa / thread so if it was OK you should have got at least 230 after the adjustment as IIRC it was 215 before too
now it's certain that the engine is boosting enough cos the overboost limit is ar 1.42 bar so if it kicked in at 240 MAP the AAP was 98 and the engine boosted more... so now all you must do is to make it reach at least 230 MAP at full load but 235 is even better and then the stall test should pass well too
I just tightened it another 1.5 turns. Now 9 threads showing and still only see 215kPa.
Ordered a new one to try.
So sorry to hear that you are still having trouble with this.
Getting it off is relatively easy, putting the bolt in that you have to tighten at the rear is a bit of a PITA.
If i was certain a different turbo would fix it then I'd splash a bit more cash.
Yes but to get the boost I had to wind the wastgate actuator in way more than I should. Limiting the amount the wastegate opens quite a lot more than is normal to get the same level of boost, or gas flowing through the turbine side with less being bypassed. To me that points to issues there somewhere.
I must insist, as long as it goes to overboost IMO it's not the turbo, tigthen the wastegate until overboost then one thread back at a time untill it doesnt then it should go to around 1.35 bar boost...
I have it running up to 230kPa MAP/130kPa boost, with 5 threads showing on the wastegate.
and with that value you still get low power result on the stall test? .... and confirm whne you checked the injector adjustments did you undo the adjuster screw as when the rocker arm was at full stroke the injector's plunger was loose then tightened untill the plunger bottomed out then one turn back?
Yes, stall test still 2200-2300rpm.
Very strange, i must admit that i'm running out of ideas, it's very strange to be low power at normal boost even if for that boost more throttle than normal is needed.... what's the air flow and IAT reading at full boost
Do you not think, at all, that the stall test indicates a problem with the torque convertor? As that is the normal received wisdom.
