Quick background, I have been working on building a more track focused 09 JCW based on a GP2 “clone” that I bought last year. The car has been great, but I felt that a little more horsepower wouldn’t hurt especially for my local track (COTA). I recently picked up another 09 JCW (non-running) at auction that happened to have few extra goodies including a much larger turbo (60mm impeller), larger intercooler and 3” downpipe. Initially I thought this was a very aggressive set up but decided to switch things out (before spending more money on a FrankenTurbo) and look at tuning it if it was drivable. Since the turbo wasn’t new, I replaced the bearings, tested the wastegaste, and added a new Forge diverter valve.
I completed the switch over (Turbo, IC, exhaust) and the car fired right up without any alarming noise. Took it for a spin and immediately sensed that something wasn’t right since the car had no power and quickly went in limp mode. Popped the hood and noticed that the wastegate wasn’t closing so I went though the vacuum hoses looking for a potential problem, everything looked ok. I jumped the vacuum pump to the wastegate actuator and it immediately closed…so moved on to the wastegate controller. Even though I was dubious it was the problem, I replaced it as I had a spare and the cleared faults. No change, wastegate still doesn’t close.
I am not sure what my next steps should be, I have tested the vacuum hoses, they look fresh (not collapsing), tested the vacuum diaphragm of the wastegate, everything open and closes as it should, vacuum pump works, no leaks….
At idle I can see a small pulsation of the wastegate actuator – very little or no vaccum at the hose…but does feels like it is pulsing.
Considering that my car was running fine before the switch out I am confident the problem is related to the turbo and wondering whether this the ECU driven situation which is seeing something outside of expected and keeping the wastegate open? Could a larger turbo create such condition? I do plan to take to car to the dyno but really don't want to waste the time if the turbo set up is way out of spec for an engine of this displacement.
I completed the switch over (Turbo, IC, exhaust) and the car fired right up without any alarming noise. Took it for a spin and immediately sensed that something wasn’t right since the car had no power and quickly went in limp mode. Popped the hood and noticed that the wastegate wasn’t closing so I went though the vacuum hoses looking for a potential problem, everything looked ok. I jumped the vacuum pump to the wastegate actuator and it immediately closed…so moved on to the wastegate controller. Even though I was dubious it was the problem, I replaced it as I had a spare and the cleared faults. No change, wastegate still doesn’t close.
I am not sure what my next steps should be, I have tested the vacuum hoses, they look fresh (not collapsing), tested the vacuum diaphragm of the wastegate, everything open and closes as it should, vacuum pump works, no leaks….
At idle I can see a small pulsation of the wastegate actuator – very little or no vaccum at the hose…but does feels like it is pulsing.
Considering that my car was running fine before the switch out I am confident the problem is related to the turbo and wondering whether this the ECU driven situation which is seeing something outside of expected and keeping the wastegate open? Could a larger turbo create such condition? I do plan to take to car to the dyno but really don't want to waste the time if the turbo set up is way out of spec for an engine of this displacement.
