Hi all, can anybody help with this one .The vehicle came to me with a intermittent fault that would usually show itself when hot or after a long drive. Its only got 33,000 miles on it The lights for drivetrain [gear symbol]and traction control come on and vehicle goes into limp mode The fault codes are P2598-00 =boost pressure sensor A performance stuck low, and a code in the ABS U0401-00 =invalid data from ECM.switch off and restart all's fine until the next time it happens. I have done the following. Fuel system check,EGR cleaned out, intake manifold off and cleaned [done this to replace glow plugs also had codes for 2 of them]no air leaks all wiring unplugged/cleaned. The system comprises of a vacuum controlled turbo actuator [non variable vane turbo] with a electrical sensor on it to detect position. a boost pressure sensor which is the one that is termed A"now comes the bit I don't understand if I unplug the vacuum solenoid that controls the actuator I get the same 2 fault codes . if I unplug the pressure sensor I get [sensor A circuit high]I have scoped this sensor as a generic test waveform and signature tests tell me its ok 1.4 v at idle and 3.3 v at rpm
I removed the actuator to check that was ok removed position sensor all good whilst I had it off I adjusted the actuator rod 1 turn in to see if conditions alter the fault codes appear within a minute of driving but only if I accelerate a bit lively. Put actuator rod 1 turn out from original and same thing. put it back to original no faults but will have to take on long drive coz I suspect it isn't cured any help appreciated.my minds boggled at mo due to a Toyota avensis that customer booked in for electronic handbrake fault warning and turned out to be VVTi problems!!!