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Discussion Starter #1
Hey everyone. I had a mini jtd project applied last month. We get around 210 hp at crank with 1.55 bar turbo boost with revised injectors and 2.5" full chrome exhaust with a silencer at the end.

Problem is, after 2 weeks there had been some rattle noise from the engine side at no-load. While on load around 2000 rpm these sounds were being more intense and lost. I got suspicious from engine bearings and made car moved the service without passing time.

They checked it at the service and yes! it was two of engine bearings's sound. Engine has been researched and they said piston and rods were not involved. So only engine bearings changed.

What else could be problem? They said maybe an old problem of engine came up after tuning. I've got oil pump pressure checked it was 3 bar at no-load, on-load it was around 6-7 bars. So we decided that oil pump is fine too. Should I change oil pump?

Oil was changed a month ago, but we did change it again as factory standards. I have installed turbo boost pressure gauge + oil pressure one too. Is checking it with oil pressure gauge enough to do at this rate?
 

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The pulleys on the belt-end of the engine can go bad and give a rattle at low engine speeds... I had an alternator and a crank pulley go bad on me and cause a lot of noise when stopped idling, but that seemed to disappear once up to normal road speeds.
 

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Discussion Starter #3
The sound you mentioned is available too. But they said (from the service i wanted them to check belt too) nothing about belt or pulley.
 

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Discussion Starter #5
Yea, no engine oil level warning. And it's level was ok.

For 25k kms I have used Petronas syntium cp 5000 5w30 which has API SN,ACEA C2 according to mechanic's advice for 3 times.

Then I have modified turbo, 2.5 " full chrome exhaust and injector nozzle change. With these processes I used selenia 5w30.

After 1000km these sounds came up. Made car pulled to service and they said two of bearings are worn. they said pistons or rods are fine only bearings were involved so they changed bearings.

I was suspicious about oil pump and made it checked too, according to check on idle oil pressure was about 3 bars , on load about 3000rpm it becomes between 6-7 bar. So they said oil pump is doing its work.

Reading net about this and some people say engine will get rectified anyway, some of them say oil pump shoul be changed however the situation is.

Did I use wrong oil so this came up? Is this problem gonna get me whole engine cost?

I have mounted oil pressure gauge of aem to see how pressure is. Is it enough? Should I mount oil temp gauge too? To see how engine oil durability?thanks.
 

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c2 isn't sufficient by far for the power you're running.

C2 has a lower oil film strength than C3.

A3/B4 has the same oil film strength but more anti-wear and detergency/dispersancy chemistry. Without a soot filter there's absolutely no reason to run C2/C3
 
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