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S280 issue

Messages
3
Likes
5
Location
Glen Burnie, MD, USA
#1
I installed an S280 about 8 months ago and I’ve been trying to chase an overboost issue. Can’t seem to figure it out I’ve replaced the boost solenoid, I’ve replaced the waste gate, verified all lines are tight and routed correctly. I set my preload to 1mm-3mm and no matter what I end up with 24 psi on my base map. If anyone could help it would be much appreciated.
 


xxiaze

Active member
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Location
West Bend, WI, USA
#2
Did you install it yourself? If you've already check all those things I would highly consider checking for an exhaust leak at the turbo flange connecting your turbo to the exhaust manifold. If you have a small exhaust leak there it can cause these issue. Also so can restrictive catalytic converter or other exhaust back pressure issues. I dealt with the same thing on my EWG peron setup and it was a leak between my Garrett g25-550 turbine housing vbands. Check all your connections near the turbo for an exhaust leak. If that means you need to uninstall and reinstall, which was my case, then that's what you'll need to do. Happy hunting, and sorry to hear about your situation! I know the pain well.
 


OP
J
Messages
3
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5
Location
Glen Burnie, MD, USA
Thread Starter #3
Did you install it yourself? If you've already check all those things I would highly consider checking for an exhaust leak at the turbo flange connecting your turbo to the exhaust manifold. If you have a small exhaust leak there it can cause these issue. Also so can restrictive catalytic converter or other exhaust back pressure issues. I dealt with the same thing on my EWG peron setup and it was a leak between my Garrett g25-550 turbine housing vbands. Check all your connections near the turbo for an exhaust leak. If that means you need to uninstall and reinstall, which was my case, then that's what you'll need to do. Happy hunting, and sorry to hear about your situation! I know the pain well.
Yeah, I installed it. I’m also catless straight pipe so I have no restrictions I will take a look at the areas you mentioned. Appreciate it
 


Se7eN

Senior Member
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Location
San Juan, Puerto Rico
#4
Yeah, I installed it. I’m also catless straight pipe so I have no restrictions I will take a look at the areas you mentioned. Appreciate it
Have you tried Economy Mode as it is set a 0% for the WG? Maybe the base map is not set at 0%. Would allow you to see the actual preload depending on WG if its the OG should be no more than 6 PSI, if its a Turbosmart should be 14 to 15psi. Also don't test this al the way to redline, 4500rpms should be more than enough.
 


OP
J
Messages
3
Likes
5
Location
Glen Burnie, MD, USA
Thread Starter #5
Have you tried Economy Mode as it is set a 0% for the WG? Maybe the base map is not set at 0%. Would allow you to see the actual preload depending on WG if its the OG should be no more than 6 PSI, if its a Turbosmart should be 14 to 15psi. Also don't test this al the way to redline, 4500rpms should be more than enough.
I have the 14 psi turbosmart gate. My WGDC is 0% on my logs.
 


Messages
103
Likes
89
Location
St. Louis, Missouri, USA
#7
You cant expect to change wastegate and have proper boost control with no tuning. Wastegate contorl is one of the most complex control schemes with the most tables devoted to it on the whole car. I pay to have my fiesta tuned, but before I grew old and lazy, I used.to time my own cars. I wouldn't be surprised if there were 30 tables from 16x16 to 1x1 and everything in between devoted to boost control on the fiesta.....

That's why some tuners demand a certain wastegate/spring, and/or charge more for big turbo tunes. They don't want to build maps from the ground up for various wastegates and springs.
 


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dhminer

2000 Post Club
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Burlington, NC, USA
#8
Are you sure the solenoid is plumbed correctly and that the vac lines are all in good shape? Didn’t @Rocketst get high boost from melting a vac line so the gate actuator wasn’t getting any pressure?
 


PhoenixM3

Senior Member
Messages
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510
Location
Colorado Springs
#9
I installed an S280 about 8 months ago and I’ve been trying to chase an overboost issue. Can’t seem to figure it out I’ve replaced the boost solenoid, I’ve replaced the waste gate, verified all lines are tight and routed correctly. I set my preload to 1mm-3mm and no matter what I end up with 24 psi on my base map. If anyone could help it would be much appreciated.
Triple check the hoses on the solenoid. If your boost is coming on way early, hoses are swapped and that is your problem.
 


Messages
103
Likes
89
Location
St. Louis, Missouri, USA
#10
Are you sure the solenoid is plumbed correctly and that the vac lines are all in good shape? Didn’t @Rocketst get high boost from melting a vac line so the gate actuator wasn’t getting any pressure?
That would cause uncontrolled boost or wastegate pressure. He would be seeing max gauge pressure or around 14 to 15psi. Given the boost pressure he is seeing, I don't think wastegate plumbing is an issue. And a pre turbo exhaust leak would cause slow response and possibly low boost depending on severity.

None of the listed fixes make much sense.

He hasn't specifically mentioned he is running a tune for his turbo. But seeing as he wants lower boost than 24psi, I'd assume he isn't.

I would start with a tune for the wastegate you run if you haven't already done that. Obviously your boost is being ecm controlled, it's just not fine tuned to hit targets.

If you're not getting knock counts, heavy ign corrections, afr looks good, fuel pressure is hitting targets, and boost isn't running to uncontrolled levels, you're probably safe anyways. The ecm is smart and if all the safety strategies are intact, it's difficult for a tune the damage the engine in a modern car.

This is also all assuming you're running stock map or verified highscale sensors are reading 0 with engine off.
 


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