Bit Of A Problem

[mattye]

So yesterday arvo I was driving from my place to my GFs place up the Bruce Highway. It was raining pretty heavily but thats no problem. But all of a sudden the Stag lost power and the turbo whistle/whine went realy high pitched. On back off insted of the turbo plumback noise being a nice Chhhhhh noise it was more of a short higher pitch chh. At first I thought the turbo may have sucked in a bit of water n as a result died, so I slowed down and kept it off boost, and continued on to my GFs place (seems I had to get somewhere and by that time it was closer to her place). After a few ks though (5 or so) the problem went away and all is back to normal. So now im thinking it may have been starved of oil, as I just recently (ie.christmas eve) did a oil change and decided to try Mobil 1 0W40 (changing from Castrol Edge Sport 0W40, Which I have had no problems with what so ever). After the oil change I did notice the engine was slightly noisier n there was more vibration. So I was going to change the oil back anyway, n i have new oil sitting in the garage now.

But does anyone have any ideas of what the problem might have been?

Agree with my prognocis? Disagree?

I know its a hard one and my explanation is not the best. If it helps its a RS FOUR S.

All help is appreciated.

Thanks

Mattye

[GoldZilla]

So yesterday arvo I was driving from my place to my GFs place up the Bruce Highway. It was raining pretty heavily but thats no problem. But all of a sudden the Stag lost power and the turbo whistle/whine went realy high pitched. On back off insted of the turbo plumback noise being a nice Chhhhhh noise it was more of a short higher pitch chh. At first I thought the turbo may have sucked in a bit of water n as a result died, so I slowed down and kept it off boost, and continued on to my GFs place (seems I had to get somewhere and by that time it was closer to her place). After a few ks though (5 or so) the problem went away and all is back to normal. So now im thinking it may have been starved of oil, as I just recently (ie.christmas eve) did a oil change and decided to try Mobil 1 0W40 (changing from Castrol Edge Sport 0W40, Which I have had no problems with what so ever). After the oil change I did notice the engine was slightly noisier n there was more vibration. So I was going to change the oil back anyway, n i have new oil sitting in the garage now.

But does anyone have any ideas of what the problem might have been?

Agree with my prognocis? Disagree?

I know its a hard one and my explanation is not the best. If it helps its a RS FOUR S.

All help is appreciated.

Thanks

Mattye

Hmmm, I'm guessing that if you're still using the standard turbo, it might have spat a ceramic blade (or part of one)... If you want to investigate, then when the engine is cold one day, pull the cat converter off and see if there are any fragments of the blades in there.

[wolverine]

The first description sounds like an induction hose blowing off. Although that doesn't explain why it feels fine now.

Is there a small longitudinal split of one of the intercooler hoses that perhaps is holding shut when the engine is cooler? Check all the intercooler hoses and clamps.

It doesn't sound like an oil issue at all.

[66yostagea]

I went thru a similar episode after changing plugs. I dislodged the intak to the turbo and had similar noises. I thought the turbo had packed in. Pulled it all to pieces only to find the loose hose. Replaced the two broken manny studs and the two that broke getting it apart and I have a spare TO3.

I agree, check ALL the hoses first.

[mattye]

yeh i dont think theres a split as its driving perfectly fine as if nothing ever happened, boosts fine and drives fine. just changed the oil again. will see what happens. n ive given it a decent drive so it was up to opperating temp. i think its just one of those things. hopefully it doesnt happen again.

[mattye]

So it happened again bout 20 mins ago, again in the rain. its got me stumped. i think maybe im gona have to just pull everything apart bit by bit n put it back together. the turbo was making more of a whoooo noise by the way. maybe water is geting in a crack or split or somewhere where the seal had diminished.

[66yostagea]

Matt, good time to fit the FF plenum.

[mattye]

hahaha yeh seems like it...i just need you to put urs on then when u tell me u had no problems ill do it

[msports180]

0-40w oil in a RB seems a bit thin?

[mattye]

well nissan recomend 7.5W30 i think it is so its pretty close. Castrol recomend 0W40 or 5W30. was thinking might go 5W30 next time to compare.

Edited December 29, 2009 by mattye

[pipster11]

what he said, stock is 7.5w30, then you add one weight rating every 100,000kms (only need to change the latter number) => 0/5w40 for most stageas

why would you need to put thick oil in motors with such good tolerances from factory and still have hone marks when the motors are pulled down?

[msports180]

Ive never heard of going down after 100k's? Maybe thicker as it gets older?

Its just interesting as the oil grade i was told to use is no where near the factory quoted stuff and the motor is still fine after 160k's and oil's clean as each service.

Of the top of my head i cant remember exactly what it was, will have a look 2moro as i need to get some more as its due for a service again.

Edit: just looked in the garage have been using a 10w40 mobil, so not that far off, my bad, have dirty SR's stuck in my head not RB's.

Edited December 29, 2009 by msports180

[pipster11]

thats sweet, at that sort of k's 10w40 is fine, you could use 0w40 but it doesn't make much difference

as to the original problem, i'd say its water in something electrical

do you have a pod?

[mattye]

Yeh mate have a HKS pod. N i did have a look/feel around the pod n near by, both times it happened and couldn't see/feel any water.

[66yostagea]

I use Nulon Fully Syn. 10W/40 with Nulon addative. It has never given any problems. The addative is amazing in the amount of noise it reduces. I also use the addative in both R30s and the S13.

Edited December 30, 2009 by 66yostagea

[mattye]

I use Nulon Fully Syn. 10W/40 with Nulon addative. It has never given any problems. The addative is amazing in the amount of noise it reduces. I also use the addative in both R30s and the S13.

Whats the addative? I was thinking of sussing out an addative, but i belive Castrol already has one in it. And I'm a bit of a Castrol fan.

Also a bit of an update. I talked to a mate who's pretty good with RBs, he's also building my mates RB30 for his VL (so I trust his oppinion). And he recons its probs electrical (as pipster11 has already said). He said specificaly to check the ECU for water. So I've bought some electrical spray and I'm gona spend the arvo pulling plugs etc apart and giving them a spray.

Edited December 30, 2009 by mattye

[pipster11]

Whats the addative? I was thinking of sussing out an addative, but i belive Castrol already has one in it. And I'm a bit of a Castrol fan.

Also a bit of an update. I talked to a mate who's pretty good with RBs, he's also building my mates RB30 for his VL (so I trust his oppinion). And he recons its probs electrical (as pipster11 has already said). He said specificaly to check the ECU for water. So I've bought some electrical spray and I'm gona spend the arvo pulling plugs etc apart and giving them a spray.

vl's leak water from the bottom of the windscreen and it dribbles onto the ecu, thats holden for you so i doubt its that

water could be getting forced up at highspeed into some wiring, slow down and the water doesn't reach - just my theory anyway

giving the plugs/connectors a good clean cant hurt anyway

[mattye]

vl's leak water from the bottom of the windscreen and it dribbles onto the ecu, thats holden for you so i doubt its that

Thats actually why he said to check.

Pulled the MAF Sensor off yesterday. She was bloody dirty so gave her + connectors a clean. And I have to say, even if it wasn't the problem, a clean MAF makes a difference.

Had another look around the engine bay whilst it was running. Didn't spot anything. Thought i found a leak on one of the IC joins, but i think it was my imagination. lol . Gave it a tighten anyway.