jameswrx98

I have a jap 98 wrx and there is no boost whatsoever. Ive checked the Boost solenoid and thats fine, it seems that there is not enough pressure to open the wastegate. The turbo is spooling up fine, I'm baffled!! Any help would be appreciated...cheers

Glowplug

iTrader: (8)

You say, no boost. What is the boost gauge showing??

jameswrx98

It Idles at 30 cm/hg on the gauge and when I accelerate the gauge goes to 0, bit it wont go above 0 no matter how high the revs go

P1Drifter

iTrader: (7)

big air leak somewhere, check all your pipework

jameswrx98

I was thinking that, I've checked all the pipework in sight. Would anyone know where I'd get a diagram for the pipework?

The Zohan

Are you sure it isn't in limp mode https://www.scoobynet.com/general-te...-of-boost.html

PM someone like 'splitpin'

jameswrx98

I reset the ecu and no fault shows, Ill check the hoses again tomorrow, hopefully its a loose hose...that would explain the lack of pressure to the actuator,,,cheers

mbayley77

iTrader: (4)

Wouldnt a hose off cause lots of coughing and spluttering when trying to boost. i know when my dump valve come off it caused all manner of noises to come out the back end.....and the car

**jay**

iTrader: (1)

Hve you checked to see if the acuator has not stuck open, a big air leak would cause the car to run badly, could also be that the penny valve has come off the wastegate, would check to see the acuator is moving tho, does sound like its stuck open.
Jay

Jamz_

iTrader: (12)

If the actuator was stuck open, it would still reach 0.5 bar boost... so wont be that

**jay**

iTrader: (1)

Nope, if the bcs was faulty it would run off actuator pressure which is 0.5 if the actuator was stuck open it would produce nothing.

Glowplug

iTrader: (8)

As has been said, it sounds like a air leak/broken hose as it's not even making spring pressure. Check the inlet pipe under the i/c.

Jamz_

iTrader: (12)

Your wrong there... had my waste gate arm fall off the actuator which left the waste gate open, so there was nothing controlling the waste gate (no bsc, noting), just flapping about, produced only 0.5bar boost

joz8968

iTrader: (13)

# ...I say no boast
Let's call the whole thing off... #

**jay**

iTrader: (1)

Your gauge must have been faulty, or massive restriction in the exhaust, if you ran actuator pressure only you would get 0.5bar ie only the actuator doing the work, if you had no wastegate or week actuator then it would produce no boost unless the wastegate port was very small then you would get boost creep. i had the penny valve fall off a previous car and i had no boost whatever 0.0 on the gauge.
if it had that much of a boost leak the idle would be terrible and would be able to hear the leak quite clearly.

ukimpreza

iTrader: (9)

my old st205 did this at one point and it was the waste gate stuck open worth a look

Glowplug

iTrader: (8)

Soft **** Joz

joz8968

iTrader: (13)

lol

jameswrx98

Right guys I have no pressure from the hose going to the actuator, I might just add that I got the car rebuilt and this is the way it was returned to me, at first it would boost to 0.5 or 0.7 not the usual 1.0 bar and then sometimes nothing at all , then after a few days there was and still is no boost at all . The mechanic told me I needed a new Turbo so I got a 2nd opinion, I was then told that the turbo was mechanically sound and that it was "probably" a loose hose but this mechanic didn't have the time or the patience to work on it.

Glowplug

iTrader: (8)

Does the BCS click freely and constantly (apart from idle)?

Here is a diagram for the 3 port plumbing, check and clean all with carb/clutch cleaner.

**jay**

iTrader: (1)

If there was no pressure going to the actuator the boost would be through the roof, the actuator opens the wastegate to control the boost level.
Have you tried just running a small pipe from the compressor side of the turbo to the actuator, you should then have around 0.5-0.7 bar boost(actuator pressure)
would try that first, if still nothing then take a look at the pipework under the intercooler, could be a split boost pipe or not been put on right as you say its been rebuilt,
Jay

scottydouk

iTrader: (3)

How was the second opinion for turbo being good carried out? Did you take off down pipe to check turbine fine blades and if spins freely and same checks to intake side? not sure if when a map sensor goes down or not fitted correctly this may happen, but should log fault codes. your very first post how do you know turbo is spooling correctly?

jameswrx98

Ive cleaned all with carb cleaner and still no change, the BCS only clicked when I put the green connectors together...should it click constantly?

jameswrx98

I can hear it spinning at 3000revs, there are no faults showing and the car runs like a 2ltr non-turbo theres no misfire, spluttering etc.

Glowplug

iTrader: (8)

It should click on all but idle. If you just pick the revs up whilst under the bonnet you should clearly hear it.

When you cleaned the BCS did you remove ALL associated pipework and check for blockages/splits and confirm their location?
You could, as i think was suggested earlier, run a piece of hose from the turbo nipple to the actuator. That should give you 0.5bar and rule out the turbo and actuator being at fault.

jameswrx98

I took hose from boost solenoid to turbo nipple and joined it from nipple to actuator and still nothing, the boost solenoid isnt clicking when I rev though so I'm gonna replace that....cheers
Jim

jameswrx98

ya did that still nothing, bcs isn't clicking when i rev so gonna replace that and see does that solve it

Glowplug

iTrader: (8)

But it clicks on the test wires.

Something very wrong there then.
Either the turbo or waste gate!

jameswrx98

Yes, the bcs clicked when I connected the green plugs and nothing when i disconnected them and reved the engine...

Should the actuator move when I rev the engine? I tried to move it by hand but couldn't so I moved it with a grips...think the spring might be broken in it.

Is this an easy fix?

princey2k5

iTrader: (1)

I have a very similar problem to this! Checked BCS, clicks fine on test etc. Pipes not blocked however im unsure about the location of all the pipes coming off the boost solenoid. Does anyone have a pic of where these pipes should go exactly?

The pipe at the top of the BCS seems to be connected properly, the one coming from the right seems to be connected to actuator properly but the bottom pipe witht the resistor in it seems a bit dodge to me. Its connected to the pipe that connects up to the actuator via a t-piece which i put in because there was a ****ty bleed valve on it?