Whats the matter with my Turbo


  • Whats the matter with my Turbo

    Boost comes on…Barely..It hits at diffrent times. It does not hit hard does not boost hard. But the Turbo still spins freely and has been Dailey driven like this for over a month. What could be causing this problem, whats my best option? New Turbo??
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #2
    Wastegate sticking, leak somewhere in the system, both.
    88na2T-s13,q45 swap 12.6@110mph
    87T 2+2 auto,stock

  • #3
    Hmm. SO what is my best bet? Should i just get a new Turbo? It dosent seem like there is a leak in the system, leaning more towards the wastegate. As when You rev the engine in neutral the Turbo may boost a bit But There is no apparent wastegate movement, you dont see it move at all. Should i just take the Turbo off and see what i can do?
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #4
    when you say "hard" do you mean it does not boost to the factory PSI? do you have a boost gauge (non-factory) either in Bar or PSI? if the turbo original it could be seizing up. erratic boost can be many things, first off as mentioned, i'd make sure all the lines are intact and not loose. take the inlet off do you feel any play in the compressor shaft? probably as mentioned a sticky wastegate or a leak, but check everything, and can you give more information?
    SS #341
    "This car can be vicious, but in an unusual way, like a shark in a funny hat."
    -Jeremy Clarkson

  • #5
    Sorry about the lack of detail. Im not shure, ive never seen a boost gauge? like a stock one. There is no aftermarket one. The Turbo Does boost, But it dosent hit hard like it should i know its not that big of a turbo but my Turbo Z is alot slower than my friends N/A. I might just start taking things apart and inspecting, seeing what the shaft play is like and inspecting the hoses. Should i get back to you guys then?
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #6
    run your ecu codes first off.. that's the very first thing you should ever do when working on running problems.

    find an aftermarket boost gauge, tape it to the dash if you have to…run its own source to the intake manifold if you can, if not, tee into a larger vacuum line.

    take the intake piping off, check for shaft play in the turbo, both axial and thrust play.

    inspect the vacuum hose that goes between your turbo's compressor housing and the wastegate… it's probably dry rotted and/or cracked after being exposed to that much heat for so long.

    1988 300zxt. gt35, stance, etc. Wheels: Varrstoen ES2 18x9.5 et-13 225/40. 18x10.5 et0 245/40
    1990 jetta vr6'd

  • #7
    How do i run the codes? Also i do have a boost gauge but it's at my friends 45mins away! dang.
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #8
    Oh and by axial and thrust play do you mean, how it spins and if the shaft moves up and down, i know a tiny bit of movement is acceptable.
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #9
    http://xenonz31.com/ECUcodes.html

    axial = side to side
    thrust = in and out

    the turbo should spin freely.

    even a princess auto gauge is better than the stocker.

    1988 300zxt. gt35, stance, etc. Wheels: Varrstoen ES2 18x9.5 et-13 225/40. 18x10.5 et0 245/40
    1990 jetta vr6'd

  • #10
    I skipped the whole ECU code thing for now, because ive never worked on these cars much and thought it would be fun. Ive disasembeled all the intake stuff, i found one minor crack in a hose attaching to the charge pipe but i think i caused the worst of it, i didnt think it was leaking…until now. Im having troubles getting the pre-turbo elbow to clear, im shure ill get it here pretty soon. As inspecting the turbo all lines look intact, i tryed moving the waste gate manually and i could move it with my hand and sounds like everything is working, opening and closing, is this a bad thing that i can use my hand?
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #11
    Hold onto your seat boys.

    Code 13- Cylinder Head Temperature Circuit

    Code 21-Ignition signal missing in primary coil ( i do have Distrubutor ground disconnected)

    Code 23-Throttle Valve Switch circuit ( Car warms up and idles fine)

    Code 24-Neutral/ Park switch (What the hell, my car's a 5 speed?)

    Code 31- Just random electrical things, i can handle this.

    Code 34-Detonation Sensor

    Code 41-Fuel temperature sensor circuit.

    okay… Car just went on a 1000km road trip has been daily driven for over a month, only problem was the turbo and some exhaust leak issues. Now this, Where do i go from here. What Sensors can be swapped from my 86 N/A parts car.
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #12
    I just got the pre-turbo elbow off, this turbo spins freely and has absolutly no shaft play at all, im not shure what the problem is, where is the stock boos solenoid on these things, or do they use one? im confused!
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #13
    So for shits and giggles i turned the car on with no maf or no intake connected, car idles fine, i held the waste gate fully open while lightly reving it, the turbo was not boosting at all, im assuming due to lack of maf?, does this prove anything? What the hell is the matter with my car! i dont get it.
    1986 white turbo Z Current project
    1985 red 300zx n/a bought in Socal. M.I.A Deemed as chucky
    1986 Gold 300zx n/a the one that started it all.
    1985 turbo z and it starts again....

  • #14
    if you're holding the wastegate open, it wont build boost, especially under light throttle because the exhaust gasses bypass the turbine and go straight into the exhaust system. if the actuator moves easily, that might be the problem, there should be a decently strong spring inside the wastegate actuator that holds the exhaust port shut, forcing the exhaust gas to turn the turbine.
    and the car should idle without the maf, but after 2,000 rpms you might bog it down and stall. hopefully someone else can chime in?
    SS #341
    "This car can be vicious, but in an unusual way, like a shark in a funny hat."
    -Jeremy Clarkson

  • #15
    goddammit, i had a whole post written out then hit 'back' on my mouse and erased everything (fucking IE at work)

    anyway.

    open wastegate = no boost, that should be obvious.

    replace chts and its subharness.

    fix your distributor.

    recalibrate your tps… this causes idle and driveability issues.

    was your car always a 5 spd?

    fix the detonation sensor, it shouldn't be too difficult, it's either wiring or the sensor itself.

    either fully disconnect your fuel temp sensor, or clean the connections and test the wiring.

    DO NOT USE OR RE-USE OLD SENSORS you are just asking for trouble. get new ones from nissan.

    1988 300zxt. gt35, stance, etc. Wheels: Varrstoen ES2 18x9.5 et-13 225/40. 18x10.5 et0 245/40
    1990 jetta vr6'd