[Wilkeh]

Hey folks,

I'm new to the forum and a proud owner of a 59 plate Focus ST in Ice White

Cracking car and running some nice mods.

Currently I have an issue where when I boost the gauge goes into the red then immediately drops slightly and then re-boosts again. What could be causing this?

Here's a short video showing the issue (bad quality but you get the picture).

Any help would be much appreciated

 

[martinst]

This is quite normal from a remapped car, if you just plant your foot you get full boost then if the ECU isn't quite happy with traction & a load of other factors it backs off the boost until it is happy with them & then re-applies it, try booting it gradually & you will find it holds full boost.

 

[Wilkeh]

This is quite normal from a remapped car, if you just plant your foot you get full boost then if the ECU isn't quite happy with traction & a load of other factors it backs off the boost until it is happy with them & then re-applies it, try booting it gradually & you will find it holds full boost.

That's great thanks mate

 

[rasa bmw]

That's great thanks mate

you never said what gear etc,if its in 5th/6th from low speed,then it will do what you say,some maps are applied to a car with throttle in mind,ie quarter pedal=quarter boost.full throttle pedal down full boost etc..

 

[PeteST3]

you need an actuator depending on what map is on the car.

 

[Robbo]

That's overboost. The ECU pulls back the throttle to let the turbo come back under control and re-applies throttle. I used to get it a lot in 4th gear on Pumaspeed U412.

With the RS engine in but still on U412 it basically lives in a throttle limited state in 3rd gear. Boost target is 19 psi and the RS engine wants to do well over 20 psi. Can't wait for proper tuning for it.....

 

[danielbirch11]

How to fix this above issue

As mine is doing this in every gear thanks in advance