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Hi everyone, while driving my 1990 r32 GT-R last night, an unusual rhythmic chuffing noise from the passenger side of the engine bay started occuring as it started to come into boost at highway speeds on a slight uphill. Power was down, felt flat and lifeless. It did this a few months ago as well and i thought it was the blow off valves leaking, so i replaced them with a greedy one mounted in the factory location. The unusal thing is though if you stop the car and restart it the problem is gone and drives ok... tried turning the key off and on whist driving didnt stop the problem, it has to come to a complete stop.. Car is stock save for trust exhaust and bar and plate cooler, boost at 1 bar. Any ideas?? Spark plugs have bee changed, compression checked, injectors flowed and tested, no ecu codes have been set.

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Thanks for your reply rb26dett Im thinking turbo fault of some sort too, maybe wastegate??? does drop of on boost pressure slightly can be seen on the avcr graph. the turbos dont have excessive play no oil leaks and not noisy. Actually it hasnt done it in 2 days now and may take a month to do it again, the solution might be some new turbos!!

Check the turbo to manifold bolts aren't loose.

The tabs can work loose and allow the 4 nuts to come undone.

You may have to drop the turbo to block brace off under the car so as to get an accurate feel if it's loose.

Mine made a squealing sound , chuffing sound coming onto boost cos only 1 of the 2 were not tight.

Cheers

Ken

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