Light to mid throttle boost surge

[autox4fun]

In the image,
Throttle request stays near flat
throttle body dips
boost and wastegate dip and regain over and over
Speed trending upward smoothly


think normal driving, then getting nicely up to speed on an on-ramp boost levels 5-8psi max

upgraded to an 11 lb spring in the Tial


Car is an 11 Flex
FBO - like everything in the catalog , GH turbos, EPP hot pipes "with Tial"
knock counts are clean and negative,


anybody have a similar issue? thoughts on where to continue looking?

 

[MattC]

Following

 

[TopherSho]

In the image,
Throttle request stays near flat
throttle body dips
boost and wastegate dip and regain over and over
Speed trending upward smoothly


think normal driving, then getting nicely up to speed on an on-ramp boost levels 5-8psi max


no boost leaks that I can find, also upgraded to an 11 lb spring in the Tial


Car is an 11 Flex
FBO - like everything in the catolog , GH turbos, EPP hot pipes "with Tial"
knock counts are clean and negative,


anybody have a similar issue? thoughts on where to continue looking?

can you post the full log?  what bugs me is the jitter in the tan/brown line?  is that the RPM or speed ?

 

[StealBlueSHO]

In the image,
Throttle request stays near flat
throttle body dips
boost and wastegate dip and regain over and over
Speed trending upward smoothly


think normal driving, then getting nicely up to speed on an on-ramp boost levels 5-8psi max


no boost leaks that I can find, also upgraded to an 11 lb spring in the Tial


Car is an 11 Flex
FBO - like everything in the catolog , GH turbos, EPP hot pipes "with Tial"
knock counts are clean and negative,


anybody have a similar issue? thoughts on where to continue looking?

Literally just had this problem amongst others, but what you are describing is was the most prevalent issue that I could feel driving. It ended up being the Boost Control Solenoid which is $79.29 at your local dealer.

I swapped mine in the dealer parking lot after picking up the part.

Boost Control Solenoid - https://www.tascaparts.com/oem-parts/ford-turbocharger-boost-solenoid-bl3z9k378a

 

[TopherSho]

In the image,
Throttle request stays near flat
throttle body dips
boost and wastegate dip and regain over and over
Speed trending upward smoothly


think normal driving, then getting nicely up to speed on an on-ramp boost levels 5-8psi max


no boost leaks that I can find, also upgraded to an 11 lb spring in the Tial


Car is an 11 Flex
FBO - like everything in the catolog , GH turbos, EPP hot pipes "with Tial"
knock counts are clean and negative,


anybody have a similar issue? thoughts on where to continue looking?

Literally just had this problem amongst others, but what you are describing is was the most prevalent issue that I could feel driving. It ended up being the Boost Control Solenoid which is $79.29 at your local dealer.

I swapped mine in the dealer parking lot after picking up the part.

Boost Control Solenoid - https://www.tascaparts.com/oem-parts/ford-turbocharger-boost-solenoid-bl3z9k378a

I had two go bad in a year   but mine would opt to NOT open the wastegates or partially open and build too much boost

 

[StealBlueSHO]

In the image,
Throttle request stays near flat
throttle body dips
boost and wastegate dip and regain over and over
Speed trending upward smoothly


think normal driving, then getting nicely up to speed on an on-ramp boost levels 5-8psi max


no boost leaks that I can find, also upgraded to an 11 lb spring in the Tial


Car is an 11 Flex
FBO - like everything in the catolog , GH turbos, EPP hot pipes "with Tial"
knock counts are clean and negative,


anybody have a similar issue? thoughts on where to continue looking?

Literally just had this problem amongst others, but what you are describing is was the most prevalent issue that I could feel driving. It ended up being the Boost Control Solenoid which is $79.29 at your local dealer.

I swapped mine in the dealer parking lot after picking up the part.

Boost Control Solenoid - https://www.tascaparts.com/oem-parts/ford-turbocharger-boost-solenoid-bl3z9k378a

I had two go bad in a year   but mine would opt to NOT open the wastegates or partially open and build too much boost

Yea, I had that issue as well. Always assumed it was issues dealing tuning bigger turbos.. Until Matt at Gearhead had enough data on his turbo's from various other cars.. he was like.. something is off.. check the BCS..

 

[autox4fun]

This is a newer part ... 5K miles old.
I did a boost leak test tonight and I had a few small ones at couplers and got those locked down.


What I'm rather upset with is the fittings on the UPR catch can.  Major leaks - the 45 I was able to slide out of the hose.  I've had the kit for two years, the ends are just press fit fittings to hose - no clamps.  The current pictures on their website show worm gears hose clamps on each fittings.  I'm going to dig up my old hoses and see if I can get a set of turbos to finally hit hard. 

 

[autox4fun]

In the image,
Throttle request stays near flat
throttle body dips
boost and wastegate dip and regain over and over
Speed trending upward smoothly


think normal driving, then getting nicely up to speed on an on-ramp boost levels 5-8psi max


no boost leaks that I can find, also upgraded to an 11 lb spring in the Tial


Car is an 11 Flex
FBO - like everything in the catolog , GH turbos, EPP hot pipes "with Tial"
knock counts are clean and negative,


anybody have a similar issue? thoughts on where to continue looking?

can you post the full log?  what bugs me is the jitter in the tan/brown line?  is that the RPM or speed ?

SPEED is the Brown line

 

[TopherSho]

How blown up is that graph ?  It should not be that jittery and makes me think speed sensor ...