Boost Config

[pepifebles]

Hi guys,

continuing my personal battle with boost pressure
I dont know what happend with my oem solenoid, boost only reaches 0,7bar. I unplug solenoid to actuator hose, and inmediately get 1,4bar. Why does this happen? Its broken or need different setting?.

[gregpe]

Try to install flyback diode this may help .

[pepifebles]

Thanks for your help. That escapes me of my knowledge. This week come the new solenoid. I try my luck with it

[pepifebles]

Here is a diagram how to connect correctly boost control solenoid:

Hi guys, finally my Mac boost solenoid arrived. The wires, 1 to EMU and the other to +12 switch. What is the order of the cables? or either?

Thanks

[Jadzwin]

It doesn't mater

[pepifebles]

Its good this connections? When power is off, port 1 in, port 2 ex. Ok?

[pepifebles]

Hi, boost arrived to me

If I works in close loop, I modify boost target and boost dc correction table. Why if make change in dc ref table, ecu obey to this table?. Believe that this table was only to open loop.

[chris72]

Hi

the DC table defines the basic operation of the valve for a given rpm / throttle combination. this must be correct before going to closed loop operation
When in closed loop the boost target value is read and applied to the DC value active.
for example in open loop at 5000 rpm and 80% throttle your DC table may have a value of 70 % which will be sent to the valve resulting in a boost figure ( say 200 KPA )
now if you are in closed loop with the same conditions and a boost target of 220 KPA the closed loop will correct up from the starting value of 70 %. ( assuming your PID are set up correctly)

in practice a well setup open loop DC table is very good with the DC error correction table correctly set.
In closed loop i find boost builds a little quicker after gear changes and has less boost creep.

hope this helps

[pepifebles]

Here is a diagram how to connect correctly boost control solenoid:

Hi Jadzwin, I have connected my boost solenoid like you tell me. The problem is over over boost, my target is 1,2bar and actual boost is 1,8 or more. If check inverted output, boost back to normally, but solenoid always works, I can hear it. What value is correct in "disable output under pressure"?

Regards

[RHD]

if you are over boosting you need to lower boost DC ref table. The way i do it is to first assign the solenoid to the user PWM table and slowly increase the values and take note of the boost pressures, this gives me an indication of what DC= what BOOST, then you can use this information to set up the boost DC ref table. That way you are not relying heavily on the corrections and very stable boost can be obtained.


Note on setting up boost solenoids:

Some solenoids have a one way valve inside it is rare but i have had problems with this and i needed to change the configuration slightly

There are 3 ways you can have it working one is a simple air leak in the line, by connecting one port of the valve into a T fitting but this requires a small restrictor in the pressure side of the T fitting. Another method is by using 2 of the ports on the valve so that the actuator is connected to the common port and path that is normally open connects the pressure side to the actuator and path that opens during activation connects the actuator to the vent port.

the 3rd method is for external wast gates that use signals to both sides of the actuator diaphragm, but i will leave the explanation of that one for now

the second method as described earlier is the best solution for single port actuators.

[pepifebles]

if you are over boosting you need to lower boost DC ref table. The way i do it is to first assign the solenoid to the user PWM table and slowly increase the values and take note of the boost pressures, this gives me an indication of what DC= what BOOST, then you can use this information to set up the boost DC ref table. That way you are not relying heavily on the corrections and very stable boost can be obtained.


Note on setting up boost solenoids:

Some solenoids have a one way valve inside it is rare but i have had problems with this and i needed to change the configuration slightly

There are 3 ways you can have it working one is a simple air leak in the line, by connecting one port of the valve into a T fitting but this requires a small restrictor in the pressure side of the T fitting. Another method is by using 2 of the ports on the valve so that the actuator is connected to the common port and path that is normally open connects the pressure side to the actuator and path that opens during activation connects the actuator to the vent port.

the 3rd method is for external wast gates that use signals to both sides of the actuator diaphragm, but i will leave the explanation of that one for now

the second method as described earlier is the best solution for single port actuators.

I have set 5% dc ref table and boost don't change. Finally I changed port connection method and boost come back to normal. Port 1 boost in, port 3 atmosphere and port 2 to actuator.

Thanks for your help.

[ATS_Scott]

We use the same valve but we plumb it a little differently. I leave port#1 open, port #2 to wastegate, port#3 to Boost source. No tee's etc... If you are using an internal gate it will bypass through the solenoid when boost control is off or no signal to Solenoid. I usually don't see a change in boost until 25-30%DC, and just use open-loop for now, don't worry about target boost. If your on an external gate run the hose from port#2 to the "bottom" of actuator, and leave the top open to atmosphere.

I attached a screen shot of how I have boost set-up on the last Gen4 3sgte I tuned. Table #1 is E85, table #2 is pump gas. I have found no need to tune anything below 90% throttle, as the WG spring still controls boost in part throttle situations. It was out of WG spring on E85, hence the 100% DC at high RPM. Get everything dialed in on open loop, then you can use either simple DC correction to maintain correct target, or full closed loop using PID control.

[ATS_Scott]

[quote="pepifebles"]I dont know what happend with my oem solenoid, boost only reaches 0,7bar. I unplug solenoid to actuator hose, and inmediately get 1,4bar. Why does this happen? Its broken or need different setting?.

When you unplug the actuator Hose you will have no signal to the WG to tell it to open, so it will overboost.