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hey guys,

need some help, i drive a r33 gtst series 2 and i just got my car back from having a few things done to it, front and rear breaks were machined and pads changed, had the driving belts changed, had the rocker cover gaskets changed and had an engine clean (basically a leak down i guess), coolant flush and now i have some major issues!!!

the car idels between 500rpm and 1100rpm the turbo is overboosting (its set at 9psi and highest its goin is like 20.1psi) the car absolutley reaks of fuel and seems to be running very rich. the car has was tuned with power fc and electronic boost controller ect so there shouldnt be anything like this happening right??

i have talked to a couple of friends and 1 has said the head may be blown as the boost gauge is going from -7 to -5 and 0. i really dont know whats going on as the car was running perfectly fine before it went to this workshop. im thinking maybe someone has wound up the boost to 17.1 as that was the max when i got into it had been clocked at and the car has now sh*t itself!!! any help would be muchly appreciated.

cheers

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you need to take it to another mechanic that does skylines and get an assessment made. If they cleaned the motor [degreased and washed, you could have water in your colis/sparkplug area that could dry up and then the car will fix itself, but this doesn't explain your overboosting issues.

The other thing to check is for leaks esp where your boost gauge 'T's' into your vacuum lines, if it is disconnected then this could explain the overboosting/erratic idle.

All simple easy as stuff really.

I doubt it is a blown head gasket.

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agree go see a new mechanic

something sounds fundamentally wrong

until then, dont floor it and dont load it up

it sounds like its on unlimited boost mode

if you want to try yourself

check and trace the vac lines to your actuator (gold bulb on the turbo)

i bet its either cut, disconnected or mangled or botched boost control kit install

failing that check the PFC settings SETTING, BOOST

what does it look like in there, which one is highlighted

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hey guys thanks for the fast replys, i had a mechanic friend have a quick look at it and he thinks the wastegate in the stock turbo is melted closed or something because there is no movement wen the boost comes on from reving. all lines are connected everywhere and theres no water or moisture in the coilpak spark plug area, so not sure if a stuffed turbo would make the car have a shit idle though? but mayb this is why the car is running so rich??

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hey guys thanks for the fast replys, i had a mechanic friend have a quick look at it and he thinks the wastegate in the stock turbo is melted closed or something because there is no movement wen the boost comes on from reving. all lines are connected everywhere and theres no water or moisture in the coilpak spark plug area, so not sure if a stuffed turbo would make the car have a shit idle though? but mayb this is why the car is running so rich??

There's no way you can create boost from revving the engine that will make the actuator move (maybe some serious antilag....). the combination of all three sound to me a little like this

1- running rich at idle = possible air leak, also very little vacuum (is that what you mean by -7 to -5 to 0?) could mean the leak is part of the lines that feed to your boost gauge

2- overboosting A LOT= possible leak to wastegate actuator

3- reeks of fuel -at idle? Possible leak at the fuel pressure regulator, are there any lines tapped into this vac line? (It should be left on it's own in my opinion)

These are just a couple of ideas to get your thoughts ticking over about possibilities, but if you put the issues all together then they can narrow down your search. if you have access to an air compressor i'd put some pressure (say 10psi) into the system and find out if and where there are any leaks, paying particular attention to the wastegate actuation lines. The workshop responsible for the work might lie to do this little favour for you......

A leak down test requires putting air pressure into each cylinder at top dead centre to measure how well the rings, inlet and exhaust valves are sealing. Your engine clean may well have something to do with the issues from an electrical side of things but check the air leaks first.

Hope this is helpful for ya, best of luck.

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hey thanks for you help mate, got a hold of the guy who owns the work shop (found him in the phone book :) ) and he agreed to come out on saturday and have a look at it and try and fix it even though he never worked on the car himself and that his workshop is closed on a saturday...i guess its the least he could do.

thanks for everyones help hope it gets fixed soon. cheers

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well i took my car down to the workshop and found that the problem was something so small, it was a line that is connected to the bov that wasnt re connected!!!!

masive releife that it wasnt anything major so now the car is running great. once again thanks for the input and help you guys gave very muchly appreciated

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