Join Date: Sep 2001
Location: Istanbul /Turkey
Andreas is explain me problem.
I understand, your turbo is work very good condition ,especialy start 2800 rpm .
You must check some value first.
You drive a turbo car and spark -air and fuel value more important another cars.
When you install original eprom ,
you must check spark - fuel and air value again .
Check on the turbo label for the connected correct turbo.
You can change spark timing a bit little use with variable timimg sensor.It is place on the left side engine ,
if you look the engine front side placed right side engine and connected exthaus cam.You can make re spark timing correct value with use timing light gun.
This is make advance or retard spark timing.
You must connect a pressure gauge between fuel pipe and enjectors .You must read 2.5 bar fuel pressure ,if not correct ,you can adjusted it on the fuel pressure device.
You must connect a boost meter on the intake manifold,use with a T pipe .
You must read maximum turbo pressure 0.8 or max 0.9 bar on the boost .
where is come noise in to engine ? could you check it ? when you press accelerator on idle (no gear,no on the road or when no load) can you hear same heavy sound in the engine compartment ?
I mean ,,Q4 is use electronic boost control device ,its name is pieerburg ,if you dont use your car on the road ,when you press accelerate ,,turbo isnt activity ..