BMW 3-Series and 4-Series Forum (F30 / F32) | F30POST
>
Jb4 and leaving maf unplugged?
| 01-04-2019, 07:28 AM | #1 |
|
Lieutenant
 52
Rep 468
Posts |
Jb4 and leaving maf unplugged?
Before anyone starts in saying “bootmod3 is way better than jb4 etc” Jb4 works the best for me for what I’ll use it for, and is still a good product. I was lurking around not long ago, but believe it was on here. I thought I had read where if you’re running Jb4 and intake to keep the maf unplugged? Is this correct? If so what’s the exact reasoning behind it, and assuming it’s not going to mess with anything? Will be on a 15 335i
Thanks! |
| 01-04-2019, 07:34 AM | #2 |
|
Colonel
 1268
Rep 2,957
Posts |
If you have an aftermarket intake that doesn't jive with the JB4 (Injen for example) then unplugging the MAF may solve it
__________________
2015 335i Msport/6 JB4/EWG/E30/VRSF DP/ER CP/ VRSF Race Exhaust/ Injen Intake/Verde Axis 19x8.5/9.5 245/35/275/30 Conti Extreme CS/ H&R Sports / Motorsport Hardware Stud Conversion
|
|
Appreciate
0
|
| 01-04-2019, 07:52 AM | #3 | |
|
Lieutenant
52
Rep 468
Posts |
Quote:
Be running a burger motorsports with it. |
|
|
Appreciate
0
|
| 01-04-2019, 08:28 AM | #4 |
|
Colonel
1268
Rep 2,957
Posts |
All I know is I have JB4 with an Injen intake and with the MAF plugged in the car struggles, with it unplugged it's fine
__________________
2015 335i Msport/6 JB4/EWG/E30/VRSF DP/ER CP/ VRSF Race Exhaust/ Injen Intake/Verde Axis 19x8.5/9.5 245/35/275/30 Conti Extreme CS/ H&R Sports / Motorsport Hardware Stud Conversion
|
|
Appreciate
0
|
| 01-04-2019, 09:37 AM | #5 |
|
First Lieutenant
132
Rep 302
Posts |
I have a 14 335i with JB4 and an Injen intake. I have the MAF unplugged. When it's plugged, it has rough idles and RPM spikes when going through gears but all of that disappears when MAF is unplugged.
|
|
Appreciate
0
|
| 01-04-2019, 10:50 AM | #6 |
|
Brigadier General
 
1646
Rep 4,876
Posts |
Considering the MAF is required by the ECU to hit proper performance and efficiency targets (it defaults to a backup of alpha-n which is more of a bandaid with no MAF), you'd be better off ditching the sh*tty intake.
You're losing all air density and air temperature compensation with no MAF. It's like running a carb'd vehicle at this point. |
|
Appreciate
0
|
| 01-04-2019, 11:12 AM | #7 |
|
Colonel
1268
Rep 2,957
Posts |
the MAF is still there, just the sensor is removed. The ECU gets minimal information from the MAF sensor. Terry at Burger Tuning was the one that suggested I unplug the sensor
__________________
2015 335i Msport/6 JB4/EWG/E30/VRSF DP/ER CP/ VRSF Race Exhaust/ Injen Intake/Verde Axis 19x8.5/9.5 245/35/275/30 Conti Extreme CS/ H&R Sports / Motorsport Hardware Stud Conversion
|
|
Appreciate
0
|
| 01-04-2019, 11:43 AM | #8 |
|
Brigadier General
1646
Rep 4,876
Posts |
The design of the MAF is to have a couple heated elements which get cooled by incoming air. The ECU can determine volume/density of the air flow by the rate of those wires coloring, and meters fuel accordingly. It's the primary device for determine how much fuel to meter (it measures lbs/hour of air, injectors spray lbs/hour of fuel).
It allows the car to get optimum power regardless of air density/temperature. It also compensates for changes in engine air flow characteristics as the everything starts to wear. Perhaps from a drag strip WOT perspective you do not require it. From a daily driver perspective, I'd disagree. But to each their own... |
|
Appreciate
0
|
Post Reply |
| Bookmarks |
|
|
