Boost
Turbo Mini Forums

I ordered the 150-101, I’ll decide how to connect it after it has arrived.

Anywhere between the compressor housing of the turbo up to and including the plenum chamber so intercooler and pipework.
It's only after the throttle disk that you will see boost and vacuum.

Shane

Is putting a t in the line that goes from the plenum to the fuel pressure regulator (and ecu) an option?

Yes, and it will show boost only.

My gauge came in and I have installed it from the line between plenum and fuel pressure regulator.
I went driving and the gauge works, so far so good.
But.... when I put the pedal to the metal, maximum boost is 3,75 psi. No sign of higher boost in higher revs....
From where should the ecu get the sign of how many revs the engine is making and as a result desides that the waste gate solenoid can open up?

Edited by Yoda74 on 29th Nov, 2020.

To go back to your original issue regarding the solenoid valve. If your running the T3 Turbo that can put out over 2bar of pressure as fitted to the metro turbo block. If your solenoid valve is not working when you accelerate your world will get very exciting very quickly. however if your not experiencing the sheer terror of 30psi of boost and instead are trying to feel the extra boost the eco gives you on hard acceleration then your solenoid valve is working just fine.

Edited by Mr Joshua on 14th Dec, 2020.

Own the day

@Joshua: I’m not sure I understand what you mean.
I don’t want over 2bar, the standard 7psi on higher revs is about 0,5 bar.
If the solenoid doesn’t work the boost won’t go over 4 psi right?!

The only wires on my distributor are coming from the coil, a white and black/white one
At the coil they split and go into the wiring loom.

I found this wiring diagram from an era turbo, should be the same as an MG metro Turbo, or am I wrong?

Should be

Can a wastegate that’s not functioning properly be the cause of to low boost?
When it’s open all of the time, do I get to little boost?
Is there a way to test the wastegate and actuator?

How much pre-load is on it?

Thanks Shane.
I wonder what you mean with that last sentence, what do you mean with “half a hole”?

When you remove the arm from the wastegate, it should sit half a hole back. If you Google wastegate preload, there's a lot of info about this..

Apologise, I should have elaborated further but was rushing the reply.
As Steve says, remove the turnbuckle from the waste gate actuator, with the gate held closed with your finger the hole in the turnbuckle will be half a hole out of line so you pull on the actuator rod to refit the turnbuckle back on the waste gate and therefore pre loading it. The more preload you add e.g a full hole out of line the higher the boost pressure will become as you now have to overcome a greater preload.
I would strongly advise checking the operation of the actuator with a pressure source (as mentioned above) with a gauge, the last thing you want to do is damage something.

Shane

Makes more sense now, thanks, I hope I get time to take a look at it this weekend.

Cheers

Where does the hose that goes to the actuator come from? It’s impossible to see, enginebay is too full... but that’s a problem we all have I guess....

Its been many years since I owned a metro but I believe it is a short hose that goes straight to the turbo compressor housing.
Shane

It’s hard to see but there is a t-piece on the compressor housing, one tube from there is going to the boost solenoid, the other one I cannot see, but could go to the waste gate actuator.
I have no clue how to reach there and loosen the tube... oh joy, working on a turbocharged mini...
Going to drink a large cup of coffee first...

Edited by Yoda74 on 5th Dec, 2020.

The other hose from the T on the compressor housing goes to the waste gate actuator.

If you are only getting 3.75 psi of boost then the wastegate actuator is working perfectly. It should be running 4 psi but that isn't the source of your issue, so I'd leave all the hassle of trying to get .25 psi from the actuator for another day. The problem is with the boost modulation system, so it is either a defective solenoid (but you know that does open when 12 volts is applied), the wiring to the solenoid, the ECU, or the connections to the ECU.

You have a point there.
The approx 3,75 psi was at high revs, less at low revs.
What if the wastegate does not shut well?
And/or opens to quickly?

I just went to check the mini’s wiring and saw a connector being quite loose, it’s on top of the inlet manifold where the vacuum line goes to the the servo.
When I touched it gently the top came off ?!
Is this some kind of pressure sensor, is a new one still available and can it be the cause of the lack of power?



Cheers