Boost problems on S4 Turbo
#1
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Hello,
The car was at Mazda dealer for engin rebuild. After that, the car was not running any more.....
I have checked the engine, and build everything together. Now the car is running, but with a smal problem. There is not this "wow" of boost any more. By doing the engine, I replaced the turbo charger (the car has over 140.000km on it) couse the charger has had a deffectiv turbowheel. I have also removed both catalytic converter. Now the car is running well, but depending on the "new" car, there is not so much boost on it any more.
By looking at the boost gauge, the pointer point to about 3 mm befor the maximum. (+40 on display). I conclude, that there is enough of boost from turbo charger. But the boost as it was presented befor is not there any more.
I checked the trotel sensor, but it is OK and working well. Vakuum tubes are OK to. (checked them all)
The car has NO CATALYTIC converter.
Do you have an idea, what I should look after next?
Regards
Iwan
The car was at Mazda dealer for engin rebuild. After that, the car was not running any more.....
I have checked the engine, and build everything together. Now the car is running, but with a smal problem. There is not this "wow" of boost any more. By doing the engine, I replaced the turbo charger (the car has over 140.000km on it) couse the charger has had a deffectiv turbowheel. I have also removed both catalytic converter. Now the car is running well, but depending on the "new" car, there is not so much boost on it any more.
By looking at the boost gauge, the pointer point to about 3 mm befor the maximum. (+40 on display). I conclude, that there is enough of boost from turbo charger. But the boost as it was presented befor is not there any more.
I checked the trotel sensor, but it is OK and working well. Vakuum tubes are OK to. (checked them all)
The car has NO CATALYTIC converter.
Do you have an idea, what I should look after next?
Regards
Iwan
#3
make sure you stay off boost until it's worn in.
After that, check for vacuum/boost leaks. Did you put new o-rings on the injectors? That's the first place. New gaskets everywhere? Everything is tight? Spray some carb cleaner around.. if the idle changes, you've found a vacuum leak.
After that, check for vacuum/boost leaks. Did you put new o-rings on the injectors? That's the first place. New gaskets everywhere? Everything is tight? Spray some carb cleaner around.. if the idle changes, you've found a vacuum leak.
#4
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Thread Starter
Thanks for you answers,
at idle speed the motor runs verry well. If there would be any leaks the engin would not run smoothly.
The boost hold the hole time.
I did not compression test right now. Its a problem to check the compression here in Germany, couse no one own a compressiontester.
Regards
Iwan
at idle speed the motor runs verry well. If there would be any leaks the engin would not run smoothly.
The boost hold the hole time.
I did not compression test right now. Its a problem to check the compression here in Germany, couse no one own a compressiontester.
Regards
Iwan
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