Pretty sure my turbo is busted

[MackG]

First off I drive a 97gst spyder. Secondly I apologize ahead of time if this is a topic covered somewhere else in a FAQ or something but I looked around through some threads and didnt see anything that blatantly covered my question. I also did a search for broken turbo and didnt really find what I was looking for.

I started noticing about a month or two ago that sometimes when I gave my car gas the engine would rev but it wasnt transferring to the wheels so I thought my clutch was starting to go bad. I noticed that at first the problem seemed to go away whenever I filled my gas tank and would show back up as my gas depleted but I thought maybe it was a coincidence because the lack of power to the wheels really felt like the clutch was giving out. However I thought it was odd because the clutch always engaged fine and it drove fine except when I would get to about 3k rpms and then power would stop going to the wheels then it would be fine again. All this time Im thinking my clutch is about to crap on me.

Finally Im driving around trying to get a good feel for what is going on and I notice that the lack of power is coming right at the times when the turbo would usually be kicking in. I look to the turbo guage and notice that the needle isnt moving all the way up like it used to and it occurs to me that maybe its my turbo taking a crap on me. After more driving Im convinced that its my turbo that has gone kupput and not the clutch.

So should I still be able to drive even with the turbo disfunctional? What are signs that your turbo is on its last leg? Im guessing the loss of power would be the most obvious sign but because the engine was revving but not transferring power to the wheels I was suspecting the clutch. Is that a common sign that the turbo is about to give up the ghost? Also the boost needle is moving very little. Basically Im now pretty sure its the turbo but I just want to be sure and I dont want to take it to a mechanic so they can tell me 1000 other things that need to be fixed.

Finally if the turbo is the problem what should I do. I dont really want to buy a used turbo so where do you guys recommend I buy a new t25 from. Can I safely buy a used one without worrying about it going out in a month. Next question is whether turbo replacement is something I should definitely take to a certified mechanic to get fixed and what should I expect to pay. The extent of my mechanical capability is changing oil and brakes and I once installed an aftermarket airfilter on a Z28 I owned. Im suspecting this job is significantly more difficult and not a job for a mechanical novice.

Thanks in advance.

 

[Locke]

Sounds like your turbo took a crap to you. Pull the intake pipe off the turbo, and try to wiggle your compressor wheel. There is very little tolerance for play here. Give it a spin, it should spin freely with almost no resistance.

The most difficult part of replacing the turbo is getting the fasteners off without breaking them. Removing the turbo is within most people's abilities, but make sure you have tooling available to repair/replace broken studs, should this happen.

 

[yokotabrat]

Actually, a lack of power like you describe doesn't necessarily point to the turbo being bad. The easiest way to tell if a turbo is bad is by examining the amount of shaft play on the compressor wheel. You'll need to remove the air box and intake tube going to the turbo. Then you reach in and grab the center nut that holds the compressor wheel on and try to move it up and down and in and out. The turbo should have some slight up and down movement and no in and out movement. Also, look down there and verify there aren't any fins missing/chipped, and that the wheel isn't leaving scraping marks on the housing from contact. Usually, when a turbo goes, though, it'll start making a high pitched whine or blow a ton of smoke because the internal seals have gone bad.

The turbo boost gauge is really only a calculation from the ecu on how much air is going into the engine. If it's not going up as high as it once was, I'd start looking into intake or exhaust restrictions. Maybe you have a clogged air filter. Maybe the catalytic converter has melted and become a restriction. Probably also a good idea to do some maintenance like plugs and wires if they've been on there for a while.

Also, a good test for the clutch is to get on the highway and try romping on it in a higher gear like 4th or 5th. If the clutch is slipping, the rpms will go up fairly fast when you're accelerating, and then if you immediately let off the gas (but don't push the clutch in), the rpms will drop, sometimes quite a bit. If the rpms don't drop, the clutch is more than likely holding.

Hopefully this makes sense and helps some.

 

[1gDSM4g63]

Based on your description is looks like your turbo is gone. I wouldn't recommend getting a used turbo. Just go with a 16G. It is a straight bolt-on turbo.

 

[DSMboostin15]

Based on your description is looks like your turbo is gone. I wouldn't recommend getting a used turbo. Just go with a 16G. It is a straight bolt-on turbo.

It's only a bolt on for 1g cars. 2g's need an install kit. To the original poster, have you checked the wastegate? I had a similar problem on mine where the car wouldn't build boost and my boost guage would read 0. Turns out that the wastegate arm disconnected from the wastegate flapper. If that doesn't turn out to be the case, then the turbo is most likely a gonner.