turbo whining..

[fukusdm01]

Hey guys I've searched many times about the awful turbo death whine but I'm kinda doubting that I blew my turbo. I just finished my swap about a month ago and my turbo is a rebuilt t25. It was running perfectly until about a week ago i was driving home and i had to go over some damn speedbumps, I went over them slowly but when my back tires went over my exhaust hit it kinda hard. After that i started noticing my turbo whining. Do you guys think that hitting the bump caused an exhaust leak or something near the downpipe? i haven't had time to check for shaft play yet so ill update on that. Theres also no smoke or anything from the tailpipe, and im currently not driving it until i find out whats wrong. Anyone got any other things i should check? Btw its a 91 240sx with an s13 sr20det. Thanks

[1ZlowZ]

thats why you should get a flex pipe. but i dunno what it could be

[fukusdm01]

I have a megan flex downpipe. I'm so lost on how a brand new rebuilt turbo can blow that quick, I haven't even driven it hard yet.

[onesloka]

Hmm, thats odd, mine started this the other day as well. The only shaft play is the usual very small side to side. I have no smoke coming out of the exhaust, or oil in my charge pipe. When i try and boost now it makes a lot louder whistle than normal and the car feels slow. i checked for boost leaks and exhaust leaks fixed those and still.....

[Marc240]

^both of you

Check the T2 flange. Make sure the 4 bolts are coming loose between the manifold and turbo. Mine started as a death whine under acceleration only, then gets louder under boost cause the excess pressure builds up and needs to escape through a minor exhaust leak there.

Make sure no gaskets are leaking and everything is tight. Also be sure you have you support braces connected for the turbo and downpipe

[fukusdm01]

Okay I'll make sure to check that later on today. Is it possible I could've cracked my exhaust near the downpipe from that bump? The car didn't really bounce and hit it THAT hard o.O

[Marc240]

If you cracked your exhaust you would have had to been doin ALOT OF WORK!! haha

But seriously, if your exhaust is tight and firm, the whole way back. Its possible you might have slammed your downpipe somewhere causeing a leak around the turbo area? But like I said, exact same sinarieo- (did i spell that right?), same thing happened to me, then I found out my turbo was falling off.

[fukusdm01]

Lol it's scenario. But how loose was your turbo?

[Soup Nazi]

Like was stated above. Most likely the bolt backed off the turbo causing a leak. Mine did the same thing. Flex is a must. Also some put tac welds on the back of the nuts to make sure they are secure. Also you could use copper locking head nuts.

[Marc240]

the back 2 bolts between the turbo and block completely backed off. Leaving about 1/8-3/16'' gap between them, causing the exhaust leak, then while under boost, causeing the exact same whine your explaining.

[fukusdm01]

Mannn, so I gotta take off the manifold again -.- well I guess that's better than a new blown turbo. Is I possible to tighten those back bolts without pulling the manifold?

[Marc240]

Negative.

Disconnect the downpipe from the turbo elbow, then remove the manifold from the block. There should be enough room for you to slide the manifold off the studs, and be able to slip a wrench between the block and flange. The oil/coolant lines should have enough flex and play for ou to work with, not having to remove them.

Are you sure that thats the problem? Take a mirror and hold it next to the firewall and use to to look behind down there and see if you can feel/see the nuts loose or missing.

[fukusdm01]

Thank you guys for helping me out, i finally fixed the problem. It was the outlet pipe that connects to the hotpipe that had both bolts backed out of it. I guess i didnt notice how loose it was until i took the hotpipe off and shook it a lil bit. So bye bye turbo whine :D oh but one more thing im having a problem with.. my car's acceleration seems to lag a lot in first gear to second.. like it literally has no power until boost kicks in. Anyone have any idea?

[n8RPS13]

Yeah...you have an SR which = NO torque J/K

Thank you guys for helping me out, i finally fixed the problem. It was the outlet pipe that connects to the hotpipe that had both bolts backed out of it. I guess i didnt notice how loose it was until i took the hotpipe off and shook it a lil bit. So bye bye turbo whine :D oh but one more thing im having a problem with.. my car's acceleration seems to lag a lot in first gear to second.. like it literally has no power until boost kicks in. Anyone have any idea?

[Psycho 240 Freak]

Yeah, that no power until boost kicks in is called turbo lag. Common among small displacement turbo engines.

[fukusdm01]

Im talking about barely any power to even get up to 10mph o.O

[anton1o]

You really need to inspect the turbo itself.. remove the intake pipe.. Lift the rear wheels up and spool the turbo up.

Inspecting the problem with help resolve it.