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Hi guys

I've got a Jap Spec 6 speed TT which is having power issues. Firstly it is stock standard, 1995 model done just over 100000km's.

I can take off in first and it really powers out, change to second and it is dead flat. However if you let the revs drop below 3000 before powering on out of the gear change it goes real good again, until you change to third where is it dead flat again unless you let the revs drop below 3000. Same scenario occurs with every gear change.

Any Ideas?

Have changed almost every electronic, controller/servo including ECU without success. Have replaced stock BOV with brand new one - No improvement.

I have compared Boost pressures with a known good car - 1st turbo servo is boosting at about 10.5 PSI, Second turbo servo is boosting at 11.5PSI on good car but only about 3 PSI on faulty car. Swapped Servo's - No improvement. Interestingly if you attach a hand pump directly onto the second turbo servo you can manually pump the boost up to the usual 11.5 PSI and the fault is fixed. Whatever is responsible for sending the required level of boost to open that servo seems to be the culprit. Any Ideas?



A right, not a privilege
3,421 Posts
Check for pulled timing caused by knock activity from overboost in higher gears.

What is your boost control? What is your exhaust setup from the turbo back? What octane gas are you running? What does your boost gauge show?

You could try adding a few gallons of race gas when you're almost out of gas to see if it cures it. If it does, you might be getting boost creep or overboost in the taller gears.
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