Blown Turbo?

Today I put techtonics tuning's aluminum exhaust on my car (complete turbo-back). After it was all done I started the car and it sounded great. After it was running for a little it started making a harsh squeal and my buddy said I probably got some coolant on the belt and to rev it. I revved it a little and the noise got much louder for a split second then stopped. Long story short the noise kept randomly appearing at idle and I thought something was wrong. Then, when I went to drive it after putting it into gear it started making the noise again and once I started actually driving it got louder as rpms went up. The noise also kinda spooled the way the turbo would. I read a few posts on here that said a loose EGR cooler connection may make that noise as air escapes (and I removed that to get the cat out so it made sense), so I decided to just head home and check it out when I got there. A few roads down I went to go up a hill and I lost the squeal completely and a lot of power. No turbo noise or anything just loud diesel engine sound and a huge lack of power. I am 90% certain this is a blown turbo, but posting here to see if anyone has anything to input or any suggestions on how to be 100% sure.

No power could be caused by a lot of things. Routing your vac hoses wrong when reinstall will kill power. So will an old vac hose that is brittle and cracks. Not clamping a charge pipe completely will cause it to blow off, be loud and loss of power.

Go penguins!

Could you think of anything that would be caused when replacing exhaust? Maybe the lack of back pressure messed with the VNT and the ECU shut off the boost?

I really don’t think that the lack of back pressure would be detrimental to the turbo. I have been to running a straight pipe for a few years with no issues. Less back pressure should help keep the exhaust temps down a bit.

I did have a squeal when I first got my car and thought it was my turbo, but it turned out to be my Dual Mass Flywheel was coming apart. It happened when I started the car and sometimes when taking off from a stop.

Best way to determine if the turbo is the source is to pull the hoses and check the shaft for movement, you can also see if the impeller is hitting the housing while spinning. Check for excess oil in the intercooler as well which can be a sign that the seal is going.

Update: I drove to my brother's house and back (30 mins both ways) and I definitely have a whistle from the turbo, but it's not the regular turbo whistle. It's a very faint whistle. I don't think it's a blown turbo anymore, would be way louder and smokeyer. Still the same lack of power and everything, just thought I'd add that. (and it did make it there and back just fine, it was just a pain going up hills and moving from a stop) Oh, the CEL also came on on the way there, I'll scan it and post here the results. I'm expecting either a overboost or underboost.

Also, thanks for the advice PB, I'll check that stuff out tomorrow.

You put a complete new exhaust from the turbo back. Did you tighten up the 3 nuts where the new exhaust connects to the turbo. On a stock exhaust there is a metal gasket there if everything isn’t tight it can make quite a racket.

That would probably not put you in limp mode but if one of those big hoses on the other side of the turbo was disturbed or loosened during the install and not put back on properly that would put you in limp mode.

PickleRick said:

No power could be caused by a lot of things. Routing your vac hoses wrong when reinstall will kill power. So will an old vac hose that is brittle and cracks. Not clamping a charge pipe completely will cause it to blow off, be loud and loss of power.



Go Bruins !

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This ^^^ is most likely the case after just an exhaust change.


Bajan

I don't think I removed any charge or vac hoses, but I'll definitely double check them all. Does anyone have a diagram for vac and charge hose routing?

I did tighten all nuts and everything properly. I was bending the large hose that goes from the air intake to the turbo a lot so maybe it got loosened a little on the turbo side, I'll check that out as well.

On the bhw you have to remove the airbox to reach exhaust down pipe unless you have a 5 yr olds hands and arms. You had to move around vac hoses to do this. All it took for me to throw an n75 cel was bumping a brittle hose. I was in pursuit of finding oil leaks. Made it to the end of my street before it threw the cel and lost all the power past idle. Felt like a lawn mower motor under the hood vs a turbo diesel.

I didn't make any friends merging onto the freeway that morning. Limped to work. Cleared the cel and looked for hoses. Wasn't hard to find. They have cloth over them so you cant really see the crack unless the hose is hanging off the nipple. The Orileys and AutoZone vac hoses I've found are good for a year or two at best.

I run a lawn equipment shop and have access to oem stihl (dealer)fuel hose, its great stuff and i buy it in bulk. It holds up well to heat (it's used as impulse hose on chain saws) and is gas/ethanol resistant(used in 2 cycle engines) so oil wont hurt it. In a pinch tygon fuel line (a buck or two a ft) will also work but isnt as heat resistant. I have some NOS vac hose we got off a compamy that shut down that had auto inventory from the 70s and 80s, it lasts a long time. The tygon will last years. I have some poly vac hoses at the hose but the ID is too big for anything i own so i don't know how well it holds up long term.

Not much to fail on a turbo. Use a mirror and flash light or cell phone to look at fins to inspect for damage. You're gonna have oil in the charge pipes, shouldn't be more than a few tea spoons all together accumulated in the valleys. The smic may be a diffent story if it has never been removed in 200k!

You have bearings that can fail (damaged fins and possibly wont spin if too bad) and a blocked oil return drain will blow out seals and spray heaps of oil both in the exhaust and intake

A thrust bearing turbo will have some up and down play but no side to side play.

These are resilient animals and can even survive a blocked oil drain if caught in time.


Good luck, that cel will probably lead you right to the issue.


I have a pic of the vac routing on my phone at the n75 so i could remeber where they went after an engine removal. I can email them to you or text them. I have 3 diesel cars so its nice to look at another to see how they go back together when a 3 day job turns into a month.

red16vdub said:

This ^^^ is most likely the case after just an exhaust change.


Bajan

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I see what you did there.

when you were messing with the exhaust etc a turbo hose might not have been installed properly. The whistle could have been boost escaping. Check all the connections from the turbo through the intercooler all the way to the throttle body. When something happens just after you've been working it's way more likely than your turbo was fine then all of a sudden in fails just after you did a bunch of other work?? Think about the chances of that happening

Alright, checked all the vacuum lines that I messed with (the one that goes into the top of the airbox and the one that goes into the VNT actuator) and they seem ok. Scanned it and it was giving off code P0299 - turbo underboost. I also noticed that there is a very faint whistle when the car is running (sounds a lot like a vacuum leak), so I'm pretty sure something I moved around cracked a brittle hose. I'll need to do some more thorough inspection when it's less rainy and freezing outside.

I found a video of the squeal noise it was making initially. According to a post on myturbodiesel, it's just the egr pipes not tightened down all the way, so I'll take care of that once I get my underboost sorted out.
https://youtu.be/icvTdxaHn1Y

Alright, with some help from picklerick (thanks a million) I was able to discover that I missed the gasket at the intake for the pipe that connects the EGR cooler to the intake. I will get a new gasket and hopefully that will solve the issue.

PickleRick said:

I see what you did there.

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lol all in good fun


Bajan

Take the car to someone that knows more about them and let them do a proper diagnosis.

I was contemplating it, it's fixed now though.