Gta turbo - turbo sorted - now an ecu problem!!

Hi everyone, first post in the forum here.

I have a gta turbo and from day one it has never boosted as it should.

I got the advice of some mechanics I knew and also run Lee from renault alpine services and all said the same thing; accurator not functioning properly. So I had it tested and it was only opening at around 15 psi and wasn't fully open beyond 20psi. Lee told me it should open at 8 psi and be fully open at 11psi!
So, I emailed Lee again and he have me the item number to a suitable accurator on eBay. I bought it and had it fitted, only to find out I then had less boost than before. We pressure tested this accurator and it didn't move before 25psi (that's all the tool goes to) so one can only assume this accurator is not suitable and must have different opening pressures to the original?
Since, as a test more than anything, I had a bleed valve fitted where you can adjust the boost. Even in max I still get less than half boost.
If someone could help with this I would appreciate it greatly. It's been such a headache, in 3-400 quid out of pocket and am worse off than when I started.

Cheers in advance

Luke

Hi Luke .
Something not at all right somewhere .......If the actuator is not opening till 25 then you should be overboosting like mad not boosting less ......This is the link I sent and correct ,opens at 0.7 bar .

http://www.ebay.co.uk/itm/Turbo-Technic ... 0719047618

Check your small hoses from the 'turbo' plenum. If there's a split in these you will leak boost - one of them will cause you to overboost, the other will cause you to underboost.

Also check the main rubber pipes to the intercooler and the intercooler itself.

Actuator travel is adjustable - have a look in the manual.

Yes ,I've been through all this with Luke on the phone ....The last time his guys were on about fitting a bleed valve ,I said don't ,do it on the actuator .I think I quoted less than he's spent already to do the job properly but hey-ho

Where abouts in the country are you?
As everyone has already said if your actuator is operating way higher than spec.
You would be seriously over boosting I.e the car would either be flying or keep cutting out once it hits the boost limit. As both Lee's have already said this is adjustable by twiddling the bar that attaches the actuator to the waste gate, NOTE this can some times fall of. (I.e become detached and would give you a zero boost situation) so check the waste gate end is attached, if unsure what end that is check both.(but it's the opposite end to the cylindrical actuator Lhs of turbo at the bottom from memory)
I would suggest you fit a boost gauge to see what your boost is at present, this will also help by showing the negative values i.e vacuum to highlight if you have a leak.
It should as standard boost 9to10psi and negative minus 15 to 20 ish someone may have to correct the last set of figures.(there about twenty pounds on eBay. The cars dash one above the speedo is not great, but if it is going past the line you are over boosting)
If you have a boost leak you will normally hear a high pitch squeal if small, if you have a massive leak I.e the inter cooler hose has fallen of you will have no boost and the car will drive like miss daisy.
If it's accelerating you do have some boost.
Do you have any smoking issues?
To check turbo remove the intake pipe from the turbo (black bellow looking pipe one jubilee clip take you less than a minute, the other end connects to the air filter )and check compressor wheel for any damage, seizure or excessive play I.e grab the compressor nut and gentle wiggle, spin it by hand to ensure it's not seized and visually examine for serious damage.
A further thing that could be causing these problems is a stuck open dump valve. You could remove this and block of orrifice where it connects to plenum. Just leave in the engine bay attached to intake before turbo compressor.
This will show instantly if that is the problem.
Car will run fine without dump valve, some run there's permanently like this. You will just hear an unusual noise when you take your foot of the gas, sounds quite good actually.

I have a spare actuator to and a spare turbo, but you need to eliminate the easy stuff firstly.
Also while at idle you can check around the engine for leaks by using a metre of hose. Put this to your ear and then move slowly around the engine bay paying particular attention to boost pipe connections , vacuum hoses etc.(I.e place the other end of the pipe at these areas) Soapy water works too look for bubbles. The hose is basically a stethoscope listen for air leaks, also good for identifying if you have a noisy tappet which bank to adjust!

But if you live near Hampshire feel free to pop by. But you would have more success with a quick fault analysis at one of the professional alpine engineers I.e if you live near Renault Alpine Tuning Services go there or London JLEngineering go there, they will be able to quickly resolve your issues. And also point out further areas that need preventative or remedial action.

Dave

How many times did I edit that post haha I'm going to bed. Top tip buy an atmo haha iv'e edited this twice too..nightmare.

Just a thought on this. How solid is your intake pipe to the turbo? If it's collapsing under boost suction then you won't be going anywhere!

Simple test. Remove and drive. If you have boost there's your answer, if not it's a 5 minute thing.

Be careful though if your wound out to 25psi don't want to blow anything....

Jon,
There is not many here running that level of boost, well not intentionally. If his car was collapsing his intake system, I could believe yours is, it would be bloody quick then bog down.
He's implying it's not quick at all! Well at least that's how I'm reading it.
Dave

Ok so after another day of pondering over this bloody turbo boost issue I may have made slight progress.

A mechanic friend spent an hour with me and this is what he went through.

1. Took the shit boost control thing off
2. Checked the waste gate arm and accurator rod was both moving freely by disconnecting them from each other via the circlip. Both are free and move as they should.
3.He plugged an electrical boost reading device in to the pipe which comes off the acurator using a t piece and the car measured 0.2-0.25 bar
4. We wound the accurator rod in probably about half a turn and the boost level on the in car gauge has gone from 1/4 to about 1/2.


Could it really be as simple as the accurator arm being too long and thus not allowing enough boost all along? I am going to turn it in further tomorrow but it is very difficult to do as I think the thread is not very good and my grips don't get a very good grip on the rod to turn it.

My mechanic friend suspects the turbo blades are a bit worn and that was the reason for slight lack of boost before I changed the accurator on the car.

Other things to mention:
- there are no funny noises coming from the turbo. The spool up sounds as it should
- there are no obvious pipe leaks - the only split is ok the intake pipe off the turbo but it doesn't collapse under throttle.

Thank you for all your responses. I just want to get to the bottom of it!! Other than this issue the car is very good. Even my speedo works!!

Luke, changing the actuator won't relieve worn turbo blades. But it does sound as if your actuator was incorrectly set as mentioned by the two lees previously.
Also if you are unable to adjust the rod enough due to thread issue, you can fit an in line bleed valve which you could wind out this tricks the actuator and is basicaly a manual device that allows you to up the boost quickly and easily. Look it up on you tube for a better description and how to instal .

Dave

[BIG_MVS]

Welcome Luke.

Which car have you got maybe it's known in the club and might have some background on it? Some pics would be nice?

I seem to remember Turbodog mentioning winding the actuator arm in and out to up and reduce boost so it could be that someone has been there before or the actuator you have bought got wound in too much at the factory.

Hi,
Yes I understand that, but he was saying that if the blades had worn this could have been my reason for a slight lack in boost. Is this not correct?
So if this was correct I could have simply shortened the old accurator arm to compensate for the blades being worn and loosing me boost?

Bare with me here. I don't know a great deal about turbos and an learning as I go!

Again, thanks for the help.

Welcome Luke.

Which car have you got maybe it's known in the club and might have some background on it? Some pics would be nice?

I seem to remember Turbodog mentioning winding the actuator arm in and out to up and reduce boost so it could be that someone has been there before or the actuator you have bought got wound in too much at the factory.

Hi big Mvs. The reg is f700bjw. And it has 100% been on the forum before. It has a owners club sticker in the rear window and the guy I bought it from said the guy before him was a regular on here. It is grey and is absolutely standard. Although it's now got azev alloys on (didn't used to when known to forum)

Yes Luke I agree with you there,
That probably would have been your best place to start. But you really need to have a boost gauge fitted even if only temporary to resolve this.

Ok I will do that. Where can I get a suitable one from? And would it be ok to connect it to the pipe that runs off the accurator with a t-piece as I explained I did previously?