Ford Focus ST Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
Hello, folks. I'm the new one.

  • I need your concentrated knowledge.
  • I have been doing a 2015 Focus ST facelift for 3 years.
  • Stock Turbo. Turbosmart 7psi, JST tune.
I have the following problem.

The Wastegate opens sometimes and sometimes not.

I think I found out that it only works in heat. So when I made some pulls it works again.

I've already checked the small hoses and found nothing. Furthermore I changed the Pierburg pressure converter valve on the turbocharger on suspicion.

I already checked the Turbosmart 7PSI with a compressor and it works as it should and opens and closes.

Slowly I have no more ideas.

Of course it's dangerous because the WG is always closed and then 20-21 PSI at 6000 RPM are applied, which is much too much.

The turbocharger overspins enormously and the engine knocks there also quite strongly.

Could it be that the WG flap is defective and stuck ?

Does anyone have any ideas or tips?

Here's a picture for comparison... it's both the same tune.
WG STUCK.JPG


Greetings
 

·
Super Moderator
Joined
·
7,114 Posts
Hello, folks. I'm the new one.

  • I need your concentrated knowledge.
  • I have been doing a 2015 Focus ST facelift for 3 years.
  • Stock Turbo. Turbosmart 7psi, JST tune.
I have the following problem.

The Wastegate opens sometimes and sometimes not.

I think I found out that it only works in heat. So when I made some pulls it works again.

I've already checked the small hoses and found nothing. Furthermore I changed the Pierburg pressure converter valve on the turbocharger on suspicion.

I already checked the Turbosmart 7PSI with a compressor and it works as it should and opens and closes.

Slowly I have no more ideas.

Of course it's dangerous because the WG is always closed and then 20-21 PSI at 6000 RPM are applied, which is much too much.

The turbocharger overspins enormously and the engine knocks there also quite strongly.

Could it be that the WG flap is defective and stuck ?

Does anyone have any ideas or tips?

Here's a picture for comparison... it's both the same tune.
View attachment 374532

Greetings

Did your tuner say it's stuck?

Running the aftermarket wga allows you to get the results you are seeing now. It's not crazy it's literally the monster that was created. A fully adjusted stock wga (super weak) yields around 14.5-ish psi at redline. So with the turbosmart, you should be seeing quite a bit more. 20 seems a bit high, but it's been awhile since I really have heard much about people still running these aftermarket wga.

Can you give us some logs? I want to see the wgdc.

I would like to see some logs before I speculate. No reason to get you on a path, without really knowing if it's true.
 

·
Registered
Joined
·
813 Posts
Yea forgive me if I'm wrong, but are you sure your turbosmart wga doesn't need adjusted? I mean by nature as @Duece McCracken said the whole point of putting those wgas on are for better boost control set up correctly and to hold higher boost into the higher rpms. I'm not really surprised your going that high into boost at 6k, I think it sounds like your adjustment screw needs well adjusted. Your saying after you do a few pulls it starts to work, I think it's already working and what your seeing after pulls is some kind of safety into the factory logic that when it sees so high of cat temp or something it forces the wastegate open, maybe I'm way off. But I think that's why you think it's only working in heat, because your building up so much heat you're activating a safety to override the setting of the wga. And again I'm prolly way off. But I think your wga arm needs adjusted and maybe your duty cycle.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #4
Thanks for your help.

The car was tuned after the installation of the Turbosmart. Tuner is Brian from JST.

He thinks it could be a defect in the vacuum hose. But I checked them.

Car also ran for a while always clean with 30 lbs at 6k . That was so 18 PSI on average.

25 Psi at 3000 falling about 18 psi at rev ltd.

Car also runs 2 or 3 days normally and then he hangs again.

I couldn't attach a CSV file here so I uploaded it to datazap.

Datalogs...



High Boost


Good Boost

Greetings.
 

·
Super Moderator
Joined
·
7,114 Posts
no one has any idea here.
It's weird that it's intermittent. If it was a vac line, it should be constant.

We have two boost control solenoids. One on the valve cover, and the other by the turbo. Then tend to lead to intermittent boost issues. You replaced one. Try replacing the other.

Did you pull the turbo to install the turbosmart?


Did you verify function on the bench before reinstalling it?

What psi did you preload the wga?
 

·
Registered
Joined
·
11 Posts
Discussion Starter #7
I just checked, the one on top of the engine is a different valve. This has to be ordered first. It is worth a try.

I just installed the Turbosmart without removing the turbo.

It is not preloaded. Of course it was adjusted.
 

·
Registered
Joined
·
1,515 Posts
I just checked, the one on top of the engine is a different valve. This has to be ordered first. It is worth a try.

I just installed the Turbosmart without removing the turbo.

It is not preloaded. Of course it was adjusted.


Is that hose on the front of that solenoid cut?
 

·
Registered
Joined
·
11 Posts
Discussion Starter #9
I actually thought they were all the same OEM numbers.

But they are different

The one below is 7.03507.03
That upside is 7.02087.03

If this makes a technical difference I do not know.

They both fit .

And no its Not Cut.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #11
All 3 rd Gear.

Correct wastegate is always the same, it was programmed that way. at least the control unit thinks so. but it is mechanically controlled and gives no feedback. So it might not work.
 

·
Registered
Joined
·
152 Posts
Like you suggested in your first post, i have a suspicion about the pivot to the actual gate itself binding, of course it is intermittent and of course will only happen when the metal of the turbo is probably 1000 degrees, so theres no way to bench test it. The reason i bring this up is, ive personally seen Borg Warner turbos have the peens that hold the pivot in place wear out, and cause the entire pivot to fall down in the housing and, in those cases, cause underboost due to the location of the valve itself. I think with the focus turbo it can't fall out of place but it can certainly start to bind if this same thing is happening.

374756
 

·
Super Moderator
Joined
·
7,114 Posts
Hello, folks. Update.

I've changed both valves now. 200 dollars gone but unfortunately without success. The problem is still there.

I am at a loss.
As @SIstomper mentioned, the wgdc is just pegged at 80 percent. It's not tapering off or anything. So it seems your wastegate is programmed to act this way.

Do you have a valet mode, or low boost map? I'd switch to it. Then while keeping an eye on boost, spool the turbo and let off if it surpasses like 15psi. This would give you a better idea if the wg is stuck or if 80 percent wgdc is causing a bit too much boost towards redline.

Its not like your tuning is asking for less boost towards redline. Its a flat demand, which doesnt make much sense to me, and doesnt help to diagnose anything. I'm leaning towards software right now.

Well, software is easier to mess with then dropping the turbo assembly. So its worth looking into.
 

·
Super Moderator
Joined
·
7,114 Posts
Well, your first log has your wgdc drop to 80 something percent and boost dropped with it. Which is perfect functioning wastegate.

Your second log has kinda the opposite, but its over a very short rpm interval.

Also your logs are cutting out at 6k rpm, which is a bit early. we normally do logs from 2500-6500, so seeing the boost at 5800 rpm then you left off but having 21 psi isn't great for boost closer to redline where you should have more dropoff.

Well, can you collect some data like this. 3rd gear pull, Floor it to 5500-ish rpm, then give it about 3/4 throttle till 6k. We should see the wgdc drop and the boost. Pulling logs at WOT throttle doesn't tell us much about your wastegate, you are demanding all the boost you can, the whole time. On the K03 it struggles with flow in the higher RPMs, if you had lets say, a 30 series Garrett turbo, the stuck wastegate would cause you to boost into the 30 plus PSI range, which would be a huge red flag. Working with the K03 makes this a bit harder, lol.

It's really looking like tuning right now.

Another check would be to disconnect the vac line from the WGA, cap off the vac line securely. If you are just running on the WGA with no preload, you should only be able to make the WGA spring pressure give or take a wee bit. So 7psi. If you can still make 23 psi without ECU control of the WGA then your wastegate is definitely stuck, lmao

I've suffered from a stuck wastegate on my 3076r, but it was stuck half open, so I could only make like 12 psi of boost, lol. Being stuck close would have been a kaboom for me.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #18
Hello friends.

There is an update. After installing the new valves my tuner adjusted the boost pressure / wastegate again.

Since then everything is ok - almost the same values every time.

So it could be that it was just too much boost and it actually got too hot.

it is now good1 PSI less than before and about 1lbs less air. but more ignition can be driven.

Thanks for your tips and help.

DataLOG new
 

·
Super Moderator
Joined
·
7,114 Posts
Hello friends.

There is an update. After installing the new valves my tuner adjusted the boost pressure / wastegate again.

Since then everything is ok - almost the same values every time.

So it could be that it was just too much boost and it actually got too hot.

it is now good1 PSI less than before and about 1lbs less air. but more ignition can be driven.

Thanks for your tips and help.

DataLOG new
Good to hear! Yeah the turbo was pushed too far out of its efficiency range with all that wgdc, lol.

Best case for sure!
 
1 - 19 of 19 Posts
Top