[RESOLVED] Dying turbo... can it be bypassed?

[jumpfroggy]

I've read a few threads, and it sounds like I have a dying/dead turbo.

I bought my car used a while ago (6 months or so), a 95 TSI AWD in very good shape (not great, but very good) almost completely stock (minus the wheels and a few cell phone mounts). On the drive home, the person behind me said they could see a puff of bluish/grayish smoke when I hit the boost. Uh oh, blown turbo seals I thought. It didn't concern me too much, as I'd planned on going 16g soon enough.

However, it's in the 20's here now and I've been trying to wait out the winter. The turbo has gotten worse, and I've started getting hesitations when I get on the boost (like running little pieces of the rumble strips on the side of the road). Since that's started happening, I've started driving without boost. However, I can now faintly hear my turbo in what sounds like hitting the housing. Not on idle, not while accelerating, but only when cruising just even... sounds like a cyclic slight scrape, or a small metal clicking sound.

I'm pretty sure the turbo has gone out at this point. Next chance I get, I'll check the shaft play. Is there a simple way to bypass the turbo just to stay off boost? I want to replace the turbo with a 16g, but I really don't want to do it in cold weather if I can help it. My first guess is to force the wastegate to be always open, maybe by disconnecting the actuator. I may have this backwards... do I need to force it open with the actuator?

Obviously I won't do anything without knowing the consequences, but I was wondering if any of you had any ideas short of full turbo replacement. I may have to suck it up and go that route (and buy a lot of hand warmers), but it'd be nice to just by pass the turbo until spring arrives.

Thanks all, any comments are appreciated.

 

[jumpfroggy]

Okay, I'm seeing more than one person who could use a bit of education here.

If all goes well and he'd done it before, he could drop the turbo in an hour. The rebuild, if he has the tools to pull the turbo apart, would be another hour or more for someone who hadn't done it before. Then he has to reinstall the turbo which will be another hour. Then you're left with a stock turbo for the same time (more) as if you upgraded).

The wastegate flapper disconnect is truly 15 minutes.

As far as needing a new ECU and such is complete horseshit. The ECU doesn't care if the turbo is boosting 2psi or 15psi. The MAS measures airflow, the CAS/CPS measures RPM, and the ECU adds the correct fuel based on that airflow reading and RPM. Low boost will not make you run rich.

Thanks for the advice kenamond.

I already listed the parts I already have in my possession waiting to go on, all I need to do a 16g swap is the turbo itself (plus a few more parts later to maximize the turbo). I don't know much except what I've read on here, but one of the few things I've learned myself is that nothing ever goes as planned. A stuck or broken bolt is really my worst fear, followed by missing a part that I'll need. No matter how simple it seems on paper, it always seems to be one rusted solid bolt that delays me for 5 hours, and eventually breaks off forcing me to improvise. I'm combing through the 16g tutorials trying to make sure I have all the parts I need, and I'm pretty sure I'm going to do the swap soon, but in the meanwhile I'd love to do this one simple thing (detaching the WG actuator arm) if it'll help my situation, which it sounds like it will.

To the (incredibly rude) person suggesting the 'easy' rebuild; the reason I'm looking for a temp fix is to *avoid* taking off the turbo just yet. If I take off the turbo, it's certainly not to spend all that time and money just to put the same turbo back on. That's also ignoring the fact that the noises coming from my turbo suggest that it may be starting to brush the housing a bit, which means I certainly wont want to reuse it. That turbo is burnt out, and will be ditched eventually, hopefully soon.

What others have stated here is definitely true; a replacement is the true answer. But it looks like I've gotten my question answered, there is a way to bypass the turbo, it's easy and effective, and it'll help my situation albeit temporarily.

Thanks to those who posted. I know this is a strange question, but I'm sure it'll come in handy for everyone in my situation. Plus, I've seen it posted before without any real answer or discussion; I found this educational. I'm going to throw up a thread about the swap pretty soon, I'll post it here for those who want to follow along. Thanks again all.

With all that's been said (including the unnecessary insults), the OP should consider what he wants to do given his own situation in terms of needing the car, having cash for a turbo, tools for installation/rebuild, etc.

That one's easy; full 16g swap + DSMlink, 720cc, see how far I can get with that on the stock AWD transmission till I go for a shep rebuild. 3 years in the planning, ever since I owned my first FWD DSM, and now I'm finally ready to start doing it on my 2G AWD. Just hoped I could wait for temps above 20-30 before I started working

 

[tkelly27]

You've got the right idea. Just trace the WG can to the flapper, and disconnect that arm. If you floor it, you might get 2psi, but you're not flooring it anyways. You've got the right idea checking your oil level.

As far as a turbo swap goes, not to toot my own horn, but within a day of owning my first DSM I took the turbo off, pulled it apart, and put it back on. The only reason it took me so long was because I didn't notice the compressor wasn't spinning, and I had to wait for the engine to cool down once I did.

 

[kenamond]

Keep in mind that disconnecting the WGA arm from the lever may not fix your smoking problem. The CHRA sees oil pressure, so if the seals are leaking, no-boost isn't necessarily going to help with that. When my T25 "went", I dumped over a quart of oil into my intercooler in a few minutes (pulling over after the turbo let go, checking if smoke was coming from the tailpipe (it was, so I shut her down), then pulling the car into my garage after the flatbed dropped the car off at my house). That's a lot of oil that's not in the motor anymore. But I had a broken turbo shaft at that point, thrust bearing pieces were in my oil pan, etc. That's why I suggested that you disconnect the arm and have someone follow you at night to gauge how much oil you burn while driving.

 

[jumpfroggy]

Keep in mind that disconnecting the WGA arm from the lever may not fix your smoking problem. The CHRA sees oil pressure, so if the seals are leaking, no-boost isn't necessarily going to help with that. When my T25 "went", I dumped over a quart of oil into my intercooler in a few minutes (pulling over after the turbo let go, checking if smoke was coming from the tailpipe (it was, so I shut her down), then pulling the car into my garage after the flatbed dropped the car off at my house). That's a lot of oil that's not in the motor anymore. But I had a broken turbo shaft at that point, thrust bearing pieces were in my oil pan, etc. That's why I suggested that you disconnect the arm and have someone follow you at night to gauge how much oil you burn while driving.

Just wanted to post an update, a while later. I (stupidly) have not yet replaced my turbo, however I have been driving with the WGA arm disconnected. Disconnecting the arm significantly helped minimize the "stumble" problem, which before would happen at anything over 1/4 throttle (really annoying). After disconnecting the arm, stumbling only happened at low revs under high load (so, shifting into 2nd gear early and then pressing the pedal to the floor, or going uphill at low revs).

However, I really wanted to take the spark plugs out since they were in the car when I bought them, and I also figured they would let me know if the stumble problem was detonation (which I was fearful of). I pulled the plugs to look, and what do you know; bosch platinum plugs. Looks like the previous owner wanted a slight "upgrade" and put those in there (or maybe the shop did). From researching on the board, it looks like our cars "don't like" platinum plugs, possibly because the hot platinum electrode can become a ignition point and contribute to pre-ignition. However, I also noticed that the platinum plugs were in very decent shape (no detonation), but were covered in what looked like hard white deposits.

I bought a set of replacement BPR6ES's (took a day to get them in stock) and threw them in. And... stumble problem gone! I just now looked up what a white deposit-covered plug means; it's ash fouling, caused by burning oil. That makes a ton of sense now, and I think I see how the cause-and-effect worked out. First, the turbo starts to wear, causing it to leak oil under high boost. That oil gets into the intake, and is burned by the engine. The burning oil causes ash fouling on the plugs, which causes a misfire situation (my "stumbling" problem). Unhooking the turbo prevents boost and causes less (I'd say almost no) oil to leak, preventing more oil from being burned. Then replacing the fouled plugs gets rid of the ash fouling and misfires. I've been monitoring the oil levels, no perceptible leaks now that the turbo is unhooked. So it looks like now I've just got an N/A engine (technically it still has a couple lb's of boost, but not much) till I replace the turbo. But at least I'm not burning oil or experiencing misfires.

Next on the list; replacing my radiator (it's falling apart from corrosion) and then the wheel hub (sounds like the motor is attached to my rear-right wheel at highway speeds). Then rip out that turbo. I love DSM's, they're... never boring.

 

[Defiant]

I don't know where you latched onto the idea that the turbo is where your burning oil is coming from. I'd more suspect rings and valve stem seals. Sounds like a used-up motor.
A smoking turbo puts out a cloud like a destroyer at Truk Lagoon.

And no, running a turbo motor without the turbo will feel like you're trying to pull a destroyer though the Panama Canal. Without the water.

 

[jumpfroggy]

I don't know where you latched onto the idea that the turbo is where your burning oil is coming from. I'd more suspect rings and valve stem seals. Sounds like a used-up motor.
A smoking turbo puts out a cloud like a destroyer at Truk Lagoon.

And no, running a turbo motor without the turbo will feel like you're trying to pull a destroyer though the Panama Canal. Without the water.

The reason I first thought it was the turbo leaking oil is that when I had a friend driving behind me, they said there was a gray-ish smoke coming out of my car whenever I'd go full throttle (ie. full boost). During normal driving, no smoke. Also, at idle, my turbo sounds like it's making faint little repeating noises, which I imagine (with no basis really) to be a sign of it failing.

I haven't done a compression test, though I probably will in the next week.

I'm curious, why would a turbo motor w/o turbo feel so sluggish? Wouldn't it just be similar to a N/A engine? Maybe I'm missing something here...

 

[Defiant]

Turbo motors are greatly de-tuned in order to survive turbocharging. Without the turbo, a 210 horsepower motor is probably making on the order of 100.

 

[bling5tatus]

Not to mention most turbo cars have LOW compression pistons.... so w/o the turbo... you're gonna be slow.

 

[MrBoxx]

As an experiment, try hooking the WGA arm up again and see what boosting does. If you still smoke, then you know you still have some unresolved issues.

Edit: How is the shaft play on the turbo? Is the compressor wheel starting to hit the housing? Any noticeable oil buildup in the IC pipes or intake pipe?