Jump to content
SAU Community

Recommended Posts

Did a boost leak test, now I'm not making any boost

Hi all. Before I start, my car is a 1997 R33 GTST with a standard turbo.

So today I decided I would perform a boost leak test while I was in fiddling with my new adjustable wastegate actuator. I only pressurised it to the point that my 5 PSI wastegate actuator opened, and I realised that my leak tester was leaking, so I stopped. I had connected the leak tester directly to the turbo inlet. Upon putting my car back together and going for a drive, I realised it was making no boost at all. The boost gauge rises until it hits zero and doesn't go any further. To eliminate my wastegate actuator from the equation I disconnected it, and then I saw a maximum of 3 PSI. 

The turbo I've been running is a used standard one that I put in when I bought the car, as I bought it with a blown exhaust wheel on the original turbo. The turbo has always made a funny high pitched whine when it comes onto boost, but it never got any worse or developed any shaft play so I didn't think anything of it. I've put over 10,000 kilometers on the turbo since putting it in. 

I took my intake pipe off to look at the turbo and noticed two of the blades have a decent sized chunk missing. Is it possible that those chunks have been missing the whole time and could explain the strange whine when the turbo spools up? I feel like I probably would have noticed the missing bits at some stage of my tinkering but it's possible that I did not. Would the turbo even create proper boost with such missing bits from the compressor turbine? If the damage to the turbo is new, how on earth would a boost leak test have damaged anything? I'm so confused about this whole thing - I'd be super grateful for some opinions from you guys.

Edited by Custard

Either way it's turbo off so get busy. When it's apart the cracked areas on the compressor should look quite bright if it's recent damage and more dull if old. Is it possible something was ingested into it?

3 hours ago, GTSBoy said:

Oh, it's f**ked.

Haha, sure is. 

2 hours ago, Dobz said:

Either way it's turbo off so get busy. When it's apart the cracked areas on the compressor should look quite bright if it's recent damage and more dull if old. Is it possible something was ingested into it?

Already was up until 2:30 last night ripping the thing out, haha. It's an S2 turbo with a nylon wheel as far as I can tell, so I don't think I'll be able to determine it that way. I had the intake off to leak test it so it's possible, but I don't know what it could have been, and I can't find anything anywhere in the piping. I gather any bits of turbo/debris wouldn't have made it any further than my intercooler, but I can't find anything in there at all. 

no, looks exactly like a nylon wheel, especially where it's broken.

Could have been something hitting it or could just be fatigue and breaking apart; they're old now and not the most durable part to begin with.

11 hours ago, Dobz said:

It doesn't really look like a nylon wheel from the colour of it. Pull the compressor cover off and take some photos. What does the exhaust wheel look like?

 

It's definitely a nylon wheel, very obvious from the feel of flicking it with my fingernail. 

7 hours ago, hardsteppa said:

no, looks exactly like a nylon wheel, especially where it's broken.

Could have been something hitting it or could just be fatigue and breaking apart; they're old now and not the most durable part to begin with.

I'm thinking either a bit of crap came through my air compressor, or perhaps the pressure from the leak tester just hit it in a way it didn't like. Whatever I did, it broke before I drove it again - nothing happened when I actually started it up and drove it. Didn't hit a single pound of boost or hear anything weird when I got it back on the road, besides when I disconnected the actuator (and since it wasn't actually producing enough pressure to open the wastegate I chalk that extra 3 PSI up to the line that I left open on the charge pipe causing a rich condition).

6 hours ago, Dose Pipe Sutututu said:

Take it out, also throw your FMIC in the bin too and drop in another one.

Send it to HyperGear for a rebuild. 

Not very helpful mate, unlike some people I don't have thousands of dollars to throw at my car. I will be thoroughly checking and cleaning all piping and my intercooler and replacing my turbo with a good condition used unit, hopefully an R34 turbo. I will also be compression testing my motor to ensure nothing got in between my valves, but judging by how my car was running perfectly and actually surprisingly peppy making zero boost I would be very surprised if anything's happened to the motor.

Edited by Custard

You'll need to pick all the fragments out of that fmic before your motor ingests all the fragments and you'll spend more than $150 replacing that fmic because a motor rebuild or swap I'm sure will cost at least 10x to 20x more than a replacement eBay FMIC.

 

  • Like 2
7 hours ago, Dose Pipe Sutututu said:

You'll need to pick all the fragments out of that fmic before your motor ingests all the fragments and you'll spend more than $150 replacing that fmic because a motor rebuild or swap I'm sure will cost at least 10x to 20x more than a replacement eBay FMIC.

 

Yes indeed, that's what I meant when I said I'd be thoroughly cleaning everything. 

1 hour ago, KiwiRS4T said:

Next time just pull the outlet pipe off the turbo and pressurize from there on.

Mmm yes, I will be doing that in the future.

1 hour ago, STATUS said:

dont bother with r34 turbo they are still useless and prone to failure.

Save up and steel wheel what you have.

 

Sorry but I'm not here for upgrade advice, I know what my options are and I can't afford to do anything else. I will be spending under $200 on a replacement turbo and getting my (only) car back on the road ASAP. Not interested in people casually telling me to drop thousands on my car. 

Steel wheel high flow will cost you $850 and will turn your broken turbo into a brand new turbo with warranty and potential for decent power down the track if you decided to go that way. Just some food for thought.


1 minute ago, admS15 said:

Steel wheel high flow will cost you $850 and will turn your broken turbo into a brand new turbo with warranty and potential for decent power down the track if you decided to go that way. Just some food for thought.

 

As far as I am aware it is not safe to be running a highflow turbo without supporting mods and a tune. which is where it gets expensive. 

Run a highflow with the stock actuator and completely remove the factory electronic bleed valve which will give you at most 0.5bar of boost.

Wise words from STATUS.. he happens to be one of Australia's tuners.

Anyhow, I still vote you replace your FMIC.. bits of metal in there could end up in your motor and cost you thousands instead of $150.

42 minutes ago, Dose Pipe Sutututu said:

Run a highflow with the stock actuator and completely remove the factory electronic bleed valve which will give you at most 0.5bar of boost.

Wise words from STATUS.. he happens to be one of Australia's tuners.

Anyhow, I still vote you replace your FMIC.. bits of metal in there could end up in your motor and cost you thousands instead of $150.

Yeah, still a lot of money to half-arse it. If I upgrade I'm going to do it properly. Don't doubt that it's sound advice but again, not interested in upgrade advice, I can't bloody afford it, so please stop.

I found a small leak in my FMIC from some recent wallaby damage that my car incurred, so I will most likely be replacing it. Unfortunately for me it is not a $150 part, it's a $330 part. More f**king money down the drain.

$330?

come on, cooling pro $186 delivered, gpi ones even less. 

nothing half arsed with a high flow with stock ecu at less than stock boost.

up to you, but you seem like a stubborn person so not sure why you're even asking for advice. 

put it another stock turbo so it blows up again, waste of time and money

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×
×
  • Create New...