markzetec

Hi all after scratching my head for a couple of weeks it's time to ask for help.
From idle to 4500rpm on WOT my cars fine as soon as you get to 4500 it knocks or pinks like mad back off the throttle so your on 0 boost and it goes away. Any amount of positive pressure about 4500 will result in the noise.
So far I have changed;
Fuel pump
Injectors
Fuel pressure reg
ECU
Coil packs
Plugs
Cleaned all neg points on engine/chassis
Checked MAF
Checked timing (was a full tooth out!!)
Boost solenoid
Map sensor
Checked all vacuum hoses
Checked for boost leaks
Run the car on actuator pressure only
Checked ECU for fault codes none
Reset ECU no diff
Pressure tested all cylinders all were 130 psi or there abouts

Anyone got any ideas????

JuergenG

Does it make that sound when you are standing still and just revving it over 4,5k rpm? Any idea where your noise might be coming from? Just wondering, since mine started to do something similar last year. Although it was at 5k rpm and more a metallic grinding noise. Haven't found a solution yet though... :/ "Check the heatshields" seems to be a common answer for this kind of problem.

Infected by sti

iTrader: (6)

Are there any aftermarket mods on the car ie inter cooler, exhaust etc, if so has it been mapped? If it is pinking or det then randomly changing parts imho will have no real bearing over it unless the ecu is seeing the correct data and knows what it needs to do.

Also what year car is it?

markzetec

Only parts non standard air filter and exhaust and it's a 94

When I first got it everything was fine it's just devolved this problem

JohnD

iTrader: (5)

Try a dose of good octane booster (NF or similar) and see if it reduces the noise. The booster should at least reduce det. to give you an idea if this is the problem.

JohnD

markzetec

I will get some ordered tomorrow along with a new clutch!!!!!!???? So much for a brand new one being fitted before I bought the car