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Burger Tuning JB4 Golf 1.8TSI MQB specific information thread

TwinDad

TwinDad

Autocross Newbie
Location
Fort Lee, NJ
Gawernator said:
FOL?
Click to expand...

Fuel open loop. With a flash tune, they change the injector cycle to add the additional fuel needed for the increased boost. Since the JB4 is tricking the ECU, upping the FOL adds more fuel rail pressure to get the additional fuel needed. When you stack the JB4 on a flash, the FOL is usually only set to 10
 
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stuntnuts

Go Kart Newbie
Location
Maine
The more I hear about "FOL" the more I feel like it's a farce. Could someone please (preferably George) explain exactly how the JB4 unit "adjusts fuel rail pressure" via only connecting to an RPM sensor and a couple of boost sensors? How is it telling the ECU to do this?

BTW, I'm not anti-JB4. I have one sitting on my shelf waiting to install with my IS20 upgrade.
 
Diggs24

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI
stuntnuts said:
The more I hear about "FOL" the more I feel like it's a farce. Could someone please (preferably George) explain exactly how the JB4 unit "adjusts fuel rail pressure" via only connecting to an RPM sensor and a couple of boost sensors? How is it telling the ECU to do this?

BTW, I'm not anti-JB4. I have one sitting on my shelf waiting to install with my IS20 upgrade.
Click to expand...

Did you forget the CANbus connection?
 
Gawernator

Gawernator

Go Kart Champion
Location
Fremont, CA
TwinDad said:
Fuel open loop. With a flash tune, they change the injector cycle to add the additional fuel needed for the increased boost. Since the JB4 is tricking the ECU, upping the FOL adds more fuel rail pressure to get the additional fuel needed. When you stack the JB4 on a flash, the FOL is usually only set to 10
Click to expand...

Thanks.


stuntnuts said:
The more I hear about "FOL" the more I feel like it's a farce. Could someone please (preferably George) explain exactly how the JB4 unit "adjusts fuel rail pressure" via only connecting to an RPM sensor and a couple of boost sensors? How is it telling the ECU to do this?

BTW, I'm not anti-JB4. I have one sitting on my shelf waiting to install with my IS20 upgrade.
Click to expand...

Me too. I feel like I'm going to have to wait for the end of the racing season before I can install the JB4 and turbo :(
 
S

stuntnuts

Go Kart Newbie
Location
Maine
Diggs24 said:
Did you forget the CANbus connection?
Click to expand...

I'm pretty sure the JB4 doesn't SEND data thru the CANbus connection, only RECEIVES it.

If that was the case, how would a JB1 send FOL data to the ECU, since JB1's don't use CANbus whatsoever. Or can you not adjust FOL on a JB1, I'm not certain?

But, I still not convinced it is anything more than a farce or a placebo effect.
 
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TwinDad

TwinDad

Autocross Newbie
Location
Fort Lee, NJ
stuntnuts said:
I'm pretty sure the JB4 doesn't SEND data thru the CANbus connection, only RECEIVES it.

If that was the case, how would a JB1 send FOL data to the ECU, since JB1's don't use CANbus whatsoever. Or can you not adjust FOL on a JB1, I'm not certain?

But, I still not convinced it is anything more than a farce or a placebo effect.
Click to expand...

If I run FOL 60 with e85, my trims hit 51 and my AFR leans out. If I run FOL 70, my trims stay below 45 and my AFR stays in the 13's. How's that a farce?
 
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stuntnuts

Go Kart Newbie
Location
Maine
Diggs24 said:
Plug C tricks the ECU into adjusting fuel pressure from data from the canbus (and AFR wire of course).

Not sure what you are implying about it being a farce? I can get the car to set a CEL for low fuel pressure by increasing the fuel open loop too high.
Click to expand...

Plug C on the original Rev1 JB1 had a blue wire only. Purple (RPM signal?) was on a separate plug, Plug A.

Rev2 JB1 and JB4 have the blue wire and the purple wire (RPM signal?) on Plug C, eliminating Plug A altogether.

So are you telling me that the blue wire on Plug C is what controls FOL?

That could very well be and makes the most sense, but I'd like verification.

Diggs, you are one of the most knowledgeable users on here and I value your opinions VERY MUCH. Please don't think I'm disrespecting you. I'm just really curious about how FOL works, everything else I understand.
 
S

stuntnuts

Go Kart Newbie
Location
Maine
TwinDad said:
If I run FOL 60 with e85, my trims hit 51 and my AFR leans out. If I run FOL 70, my trims stay below 45 and my AFR stays in the 13's. How's that a farce?
Click to expand...

Twindad, I hold you in high regards much in the way I do Diggs. I'm just asking the questions.

I would LOVE to know what the blue wire on Plug C actually connects to in the vehicle harness.
 
TwinDad

TwinDad

Autocross Newbie
Location
Fort Lee, NJ
stuntnuts said:
Plug C on the original Rev1 JB1 had a blue wire only. Purple (RPM signal?) was on a separate plug, Plug A.

Rev2 JB1 and JB4 have the blue wire and the purple wire (RPM signal?) on Plug C, eliminating Plug A altogether.

So are you telling me that the blue wire on Plug C is what controls FOL?

That could very well be and makes the most sense, but I'd like verification.

Diggs, you are one of the most knowledgeable users on here and I value your opinions VERY MUCH. Please don't think I'm disrespecting you. I'm just really curious about how FOL works, everything else I understand.
Click to expand...

I'm guessing that it sends a signal that the rail pressure is lower than what the ECU thinks it is. It then compensates by raising the pressure
 
MeltedSolid

MeltedSolid

Autocross Newbie
Location
San Francisco Bay Area
Car(s)
'15 Golf, e36 328i
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