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RB25DET stuffed - turbo maybe? Coil issue?

gatty

By gatty,
in Engines & Forced Induction

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gatty Mentor

gatty

Posted
Posted

hey guys

Car Stats:

1993 R33 GTST Auto

Blitz FMIC

Manual Boost Controller

POD

Blitz 3" Cat Back Exhaust

HKS Fuel Cut Defender

The Story:

Car was missing very badly when boosting over 5 PSI - Taped the coils as a temporary measure to see if it fixed it. Once taped the car ran perfect up to 12 PSI (we didn't try to boost it any higher due to lack of after market gauge).

For a more permanant fix owner removed tape - and used a gasket compound to seal them - apparently it's not a insulator though (how stupid!) but that cannot be confirmed as he forgets exact brand/type. Once the gasket shit was hard he took it for a drive - was running fine. He gave it a bit of a 1/4 mile run through the gears (wanna-be manual driver :rolleyes:). Just after he thrashed it a bit at 10 PSI with the gasket shit in place a HUGE cloud of white/blueish smoke came form the exhaust when he got off the gas. The car then seemed to be running VERY rough at idle - a bit like if only 6 cylinders were firing. The car still bosts - but when he gives it some smoke comes out, and a large cloud as he gets off the gas.

He turned boost back to 1 PSI roughly to drive home (about 20 mins drive), just as he got home oil pressure dropped to about 1 (from just above 4 where it usualy sits). He checked oil and it was almost empty - I assume as it had all been burnt off....

Is the motor ****ed? Turbo? whgat could cause this? Could the fact that maybe one of the coils is shorting out onto the head due to the fact a insulator was not used (maybe) cause this?

I suspected turbo - but no noise in turbo just as knocking/grinding etc - and the car still hits boost ok. There was a bit of a knocking sound in the motor a few days prior - but could only be heard with head under bonnet - and would last for about half a second just as you gave it a few revs from idle.

Any idea's guys???

OFENSV Proficient

OFENSV

Posted
Posted

check for alot of oil in inlet and exhaust dump pipe etc. carry out compression test. pulling out the plugs would tell you if you melted a piston as it would be all oily and look like it hasnt been firing. there just a few thins to check off the top of my head

55Nat Enthusiast

55Nat

Posted
Posted

Take the spark plug out of number 6 & 1 cylinder and check for lots if oil, if the plugs are wet with oil then for sure you have blown your ringlands & maby a hole down the side, Don't drive the car any more as it will only do more dammage.

Time to chuck in a set of forged piston's.

:cheers:

Nathan

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