Long time from I've posted on this site to be honest! Hoping some of the guys with turbo Altezzas or even anyone with good knowledge of turbo setups etc can help.
There's a long version of this story; to keep things simple, i'll stick to the short.
Start off with spec;
Greddy bolt on Kit (Turbo has 0.5bar actuator now as opposed to standard 0.3)
SARD 550cc injectors
Upgrated fuel pump with return fuel line and AEM Regulator
Apexi Power FC with commander (ECU)
Ok so car was over fuelling, not idling right etc. Checked sensors on commander and seen 02 sensor had no Volts - replaced 02 sensor with second hand 1 - cured problem.
Week later went to Donegal rally; needed petrol while there; car is mapped to 97 octane but only 95 octane in Donegal petrol stations (wtf!) so put in 95 with octane booster (which i didn't like doing) and tried not to boost too hard etc.
Day later car started holding back when accelerating
Thought maybe the bad fuel. Drove it easy for few days until 95 was 100% cleared out and only 97 in system.
Tried to drive it hard but could still feel it holding back and then overboosting to 0.7bar.
Checked vac lines, actuator etc etc and nothing is standing out that could be causing wastegate to stick/shut. Actuator opens and 0.5bar and holds pressure fine.
Drove car for another week or so (easy) until my tuner could check.... he checked map and has said nothing wrong that he can see and is baffled also. He thinks perhaps the MAF could be faulty causing it to read incorrectly or something but he believes its more than likely mechanical...
(I checked MAF voltages are different RPMs and compared to some i found online and they dont match. My voltages range from 1.5 @ idle to 2.8ish @ 5k RPM while sitting stationary - haven't tried a new MAF yet as i haven't been able to get hold of one.)
My next protocol was to strip down the turbo and check wastegate, turbo & manifold gaskets etc BUT before i do this was hoping to see if anyone else has had this issue before and perhaps has any ideas to what could be causing it??
May be worth noting that the car seems to be running worse these days and on 2 occasions when i accelerated, the power to the engine completely died and the EML came on for few seconds. It then went out again and power restored????
Anyway thanks in advance for any replies.