Jump to content
SAU Community

Recommended Posts

Ahh yeah as title says... as silly as it seems... I blew my old turbo and bought a highflowed one second hand. It was near new and had no shaft play. I had it quickly checked by MTQ up here and he said it looked good.

Now yesterday i put it all on exactly the same as i pulled it off... got the car running fine... except when i pull the throttle cable or go for a little drive there's NO boost and when there's meant to be boost it blows slight smoke (from running too rich from no boost i presume). The new highflow came with a hks actuator which is what i originally thought MIGHT be the problem... so i put the standard one on from the old turbo and no difference...

The wastegate valve stays shut the whole time and the shaft doesn't move at all under throttle and no spool/doesn't go above 0 on the boost gauge.

Both the exhaust and compressor wheels spin freely and at the same time (one spins the other obviously). I did have an exhaust leak between the manifold and the turbo but put a new gasket in there this morning and now it's gone.. but same problem... not going above 0 only staying in vacuum. I've checked all the intercooler pipes/vacuum lines etc etc and am now stuck. I would think it would be something fairly obvious!

So if anyone has any suggestions of what it could be please help me out... I really don't want to think it's the turbo afterall but if anyone can help me before i start pulling it all off again i'd much appreciate it!

Thankyou in advance...

Steve.

  • Replies 60
  • Created
  • Last Reply

Top Posters In This Topic

wastegate flap stuck open

intercooler pipework loose or leaking

vac lines loose or leaking

basically its leaking pressure or the wastegate is always open

thus the turbocharger nevers gets to spin fast enough and doesnt build any positive pressure

wastegate stays closed.. actuator doesn't move.. could a small vacuum leak eg in the rubber snorkel or something make it produce NO boost? It sorta sounds like there's an air-ie noise coming from that side and no not from the air filter lol. I'll keep looking but yeah.

So a vacuum leak could stop it producing boost/spooling and therefore stop the wastegate from opening???

Okay i took the rubber snorkel off from the turbo and thus removing afm as well... and started the car and it idled fine and when i rev it a bit i can see the compressor wheel spinning.. so it's definitely capable of producing boost... it's just not??:s

bov should be alright... haven't touched that at all and yeah once again it's getting no spool or positive pressure whatsoever..

Damn cars. I'm sure it'll be something really obvious that i'll kick myself for but i've checked everything 1000 times and pulled off/put on as well. hmmmmmmmmm

Hey both. I was free revving it at first then i thought no i'll take it for a drive... went about 100m up the street and back and i accelerated just hard enough to where the turbo should be spooling.. maybe went to 3000rpm but there was nothing. Was just running really rich.

It's highflowed it shouldn't be that different coming on boost pretty much same as before. The blowoff valve doesn't make a single noise either..

Alright i took it for a bit of a harder drive just then and i can get the bov to open very very slightly but boost still isn't above 0 and yeah.

When idling how fast is the turbo supposed to be spinning??

I doubt 3000 rpm is going to produce any boost. It is highly unlikely to produce any on a "free rev" (even @ 6000) . You need to load up the engine to get boost.

Also, check ALL the intercooler piping between the compressor and the throttle and confirm all the joints are intact.

Well before i could just give the throttle cable a tug and the turbo would spool and then the bov would sound... now it's doing neither... and no matter what i do/how i drive i can't get the turbo to spool or produce boost. If i go for a hardish drive down the street the boost gauge doesn't even get close to the 0 on the gauge... However both wheels are spinning, wastegate flap opens and closes when disconnected from the arm.. the actuator spring is working fine when i pull it... and hmmmm

Thanks for everyone help. I'm starting to consider the possibility that it's the turbo... Anyone else think that's a possibility?? Is the compressor wheel supposed to be slowly spinning when it's just on idle? I can concentrate on one blade the whole time it's spinning that slowly.. but if i pull the throttle it spins rapidly like you'd expect it should..

i still think its possible (unlikely i know) that it could be the compressor nut tension.

it could be loose enough that at idle & free rev it doesnt spin on the shaft but when the turbine really gets moving the comp wheel could spin/slow down & not create boost.

im not saying thats yur problem but it is possible i believe.

good luck

Well if it's that i should let it idle like before without the afm and see if the shaft is spinning faster than the compressor wheel.. I'll give that a go or see if i can tighten the nut at all.

Your boost gauge is connected / working? If it's spinning wheels, then I would hazard a guess that you have some additional power from boost happening.

Maybe it's such a large turbo that it doesn't produce boost until quite high revs and loads.

Well if it's that i should let it idle like before without the afm and see if the shaft is spinning faster than the compressor wheel.. I'll give that a go or see if i can tighten the nut at all.

no, what i mean is it might not start spinning on the shaft until the turbine/shaft is under load.

to be able to tighten the nut you will need to remove the dump, like i said this is just a suggestion to what might be wrong, hopefully its something easier.

Well i just checked all the intercooler pipes again... let it run and got a mate to yank the throttle cable and felt them all to see if I could feel any air escaping but they all seem fine and i can't get any movement out of them at all if i shake them around... all the vac lines are perfect and i can blow through all of them so there's no blockage... and they're on exactly the same as before..

Another funny thing... not sure if this is normal or not... but when i started the car the compressor wheel was spinning really slowly... then if i give it a squirt it starts spinning quickly and keeps spinning quickly even when it drops back to idle revs.... is that normal?? Is the turbo supposed to change rpm like that...

I guess thats the turbo gaining RPM and then not returning to its normal spool speed as the momentum is still rotating it (hence why people use turbo timers, to give the turbo time to reduce its RPM)

Very strange indeed. No blocked cat or something like that choking up the whole car?

Edited by Granthem

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



  • Similar Content

  • Latest Posts

    • Hi all,   long time listener, first time caller   i was wondering if anyone can help me identify a transistor on the climate control unit board that decided to fry itself   I've circled it in the attached photo   any help would be appreciated
    • I mean, I got two VASS engineers to refuse to cert my own coilovers stating those very laws. Appendix B makes it pretty clear what it considers 'Variable Suspension' to be. In my lived experience they can't certify something that isn't actually in the list as something that requires certification. In the VASS engineering checklist they have to complete (LS3/NCOP11) and sign on there is nothing there. All the references inside NCOP11 state that if it's variable by the driver that height needs to maintain 100mm while the car is in motion. It states the car is lowered lowering blocks and other types of things are acceptable. Dialling out a shock is about as 'user adjustable' as changing any other suspension component lol. I wanted to have it signed off to dissuade HWP and RWC testers to state the suspension is legal to avoid having this discussion with them. The real problem is that Police and RWC/Pink/Blue slip people will say it needs engineering, and the engineers will state it doesn't need engineering. It is hugely irritating when aforementioned people get all "i know the rules mate feck off" when they don't, and the actual engineers are pleasant as all hell and do know the rules. Cars failing RWC for things that aren't listed in the RWC requirements is another thing here entirely!
    • I don't. I mean, mine's not a GTR, but it is a 32 with a lot of GTR stuff on it. But regardless, I typically buy from local suppliers. Getting stuff from Japan is seldom worth the pain. Buying from RHDJapan usually ends up in the final total of your basket being about double what you thought it would be, after all the bullshit fees and such are added on.
    • The hydrocarbon component of E10 can be shittier, and is in fact, shittier, than that used in normal 91RON fuel. That's because the octane boost provided by the ethanol allows them to use stuff that doesn't make the grade without the help. The 1c/L saving typically available on E10 is going to be massively overridden by the increased consumption caused by the ethanol and the crappier HC (ie the HCs will be less dense, meaning that there will definitely be less energy per unit volume than for more dense HCs). That is one of the reasons why P98 will return better fuel consumption than 91 does, even with the ignition timing completely fixed. There is more energy per unit volume because the HCs used in 98 are higher density than in the lawnmower fuel.
    • No, I'd suggest that that is the checklist for pneumatic/hydraulic adjustable systems. I would say, based on my years of reading and complying with Australian Standards and similar regulations, that the narrow interpretation of Clause 3.2 b would be the preferred/expected/intended one, by the author, and those using the standard. Wishful thinking need not apply.
×
×
  • Create New...