MHD w/ N20 3.5bar help

bxbimmer88

New Member
Mar 15, 2018
3
0
0
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2007 335xi
Hey all so my car is an 07 e90 n54 engine thats fbo.

I'm having some issues getting my car to drive properly with MHD stage 2+ and this N20 3.5bar sensor. Adapter is installed. First test drive the car jerks when the car shifts from what seems to be when it shifts 2nd&3rd and 3rd&4th gears. There is no jerking during downshifts. Only up. In MHD I flashed to stage2+ with the N20 3.5bar box checked. I get these 2 codes

2ABD Intake pressure sensor, re-running
2D2E angle of throttle valve - intake pipe underpressure, correlation

I've been googling the codes and it seems I have to change some numbers or something, but I can't seem to find a direct DIY or how to. How am I supposed to get my car to run properly and not have the jerking between gear shifts?
 
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doublespaces

Administrator
Oct 18, 2016
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2009 E93 335i
What is the boost target of the 2+ map? I know if you exceed a certain threshold, you need the M Boost module. Have you tried putting the stock sensor back on?
 

morffius

Specialist
Jul 15, 2017
87
16
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Ride
135i
I have the same problem with the 3.5 sensor + BMS adapter and OTS MHD map. I keep the same map and just change the sensor and check the new sensor and refresh and immediately get the 2ABD code.
 

morffius

Specialist
Jul 15, 2017
87
16
0
Ride
135i
Make sure the DME is asleep before swapping and the flash option is flashed before changing the TMAP

Tried it this way. Did the flash option then waiting with the car off for 30 min and then replaced the TMAP sensor. Still had the same ABD error and 1/2 engine light. I have two 3.5bar sensors as well. I just picked up a new one from ECS. I will try it again tonight. Any other thoughts?
 

bxbimmer88

New Member
Mar 15, 2018
3
0
0
Ride
2007 335xi
Fyi I’ve learned that the 3.5bar has no benefits unless you have upgraded inlets on stock turbos, have aftermarket turbos, or one big turbo. The adapter from BMS is required on n54 engines.

You need to use the jb4 interface to program the 3.5bar to work correctly. If you’re using mhd you have to have a JB4 back end flash.

I ended up returning the 3.5bar as I don’t have upgraded inlets or turbos. I purchased an oem one from fcp euro.

Oh, and for whoever or whomever is trying to get he ecu to go to sleep, best option is to just unplug the battery while switching sensors.
 

morffius

Specialist
Jul 15, 2017
87
16
0
Ride
135i
Fyi I’ve learned that the 3.5bar has no benefits unless you have upgraded inlets on stock turbos, have aftermarket turbos, or one big turbo. The adapter from BMS is required on n54 engines.

You need to use the jb4 interface to program the 3.5bar to work correctly. If you’re using mhd you have to have a JB4 back end flash.

I ended up returning the 3.5bar as I don’t have upgraded inlets or turbos. I purchased an oem one from fcp euro.

Oh, and for whoever or whomever is trying to get he ecu to go to sleep, best option is to just unplug the battery while switching sensors.

I was planning on upgrading the turbos and doing the 3.5 bar in preparation. I wanted to keep everything without jb4. So there is no way to just upgrade the TMAP, eh. I need to find a better solution.
 

doublespaces

Administrator
Oct 18, 2016
9,303
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2009 E93 335i
I was planning on upgrading the turbos and doing the 3.5 bar in preparation. I wanted to keep everything without jb4. So there is no way to just upgrade the TMAP, eh. I need to find a better solution.

If you're upgrading the turbos, just get a custom tune. Usually they bake the 3.5 bar stuff into the tune and you don't need to check those boxes.
 

TheAllOriginal

Private
Dec 15, 2016
48
13
0
Baltimore, MD
Fyi I’ve learned that the 3.5bar has no benefits unless you have upgraded inlets on stock turbos, have aftermarket turbos, or one big turbo. The adapter from BMS is required on n54 engines.

You need to use the jb4 interface to program the 3.5bar to work correctly. If you’re using mhd you have to have a JB4 back end flash.

I ended up returning the 3.5bar as I don’t have upgraded inlets or turbos. I purchased an oem one from fcp euro.

Oh, and for whoever or whomever is trying to get he ecu to go to sleep, best option is to just unplug the battery while switching sensors.
3.5 bar sensor has no benefit to OTS maps from MHD lol, it's only to be able to run more boost from a custom map. Also you dont need JB4 to run the sensor, or inlets.
 

Jeffman

Major
Jan 7, 2017
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Suddenly I got the 2ABD Intake pressure sensor, re-running code and half engine dash light when staring the car. Twice in a row. Any suggestions?
 

Jeffman

Major
Jan 7, 2017
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Yes. MHD. As well as a connector from BMS. All of your answers can be found here on SpoolStreet and Burger Motorsport website. Have fun!
 

matreyia

Major
Apr 19, 2017
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335i e93
Tried it this way. Did the flash option then waiting with the car off for 30 min and then replaced the TMAP sensor. Still had the same ABD error and 1/2 engine light. I have two 3.5bar sensors as well. I just picked up a new one from ECS. I will try it again tonight. Any other thoughts?

If you replace the sensor, the battery should be disconnected. IF not, then you will have to do the throttle reset in MHD adaptations, then take the key out, and wait for a minute, then put key back in, then turn on accessory position, do not touch brakes... then wait 30 seconds, then fully turn on engine. Otherwise, you will get all kind of unholy problems.
 
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langsbr

Captain
Apr 5, 2017
1,266
771
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07 335i 6MT e90
Suddenly I got the 2ABD Intake pressure sensor, re-running code and half engine dash light when staring the car. Twice in a row. Any suggestions?

I've been getting this quite a bit, but not every start, as well. It's extremely annoying to have to clear codes just to drive the car. I would think if it was a part failure it would happen every time, but I would think the same if it was a tune issue.

Anyone ever solve the 2abd on start issue?
 

Jeffman

Major
Jan 7, 2017
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I had noticed one of the wires getting frayed leading to my TMAP sensor on the intake manifold. Straightened it out with some electrical tape, and keeping my battery charged with a battery tender keeps away the codes.
 
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langsbr

Captain
Apr 5, 2017
1,266
771
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07 335i 6MT e90
I had noticed one of the wires getting frayed leading to my TMAP sensor on the intake manifold. Straightened it out with dome electrical tape, and keeping my battery charged with a tender keeps away the codes.

I'll check for physical issues tomorrow. I have a new battery but I don't keep it on a tender and I probably should since I drive it once a week at most.

Thanks
 
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Zeezul

Private
Nov 26, 2016
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Holiday, FL. 34691
I'll check for physical issues tomorrow. I have a new battery but I don't keep it on a tender and I probably should since I drive it once a week at most.

Thanks
My issue was checking the box for the 3.5 bar sensor on mhd AND putting a "1" on the jb4 (I have a bef). I didn't know you're suppose to leave the mhd option unchecked. Got a lot of bucking, jerking in first and on low throttle with hesitation. Unchecked the mhd option, reflashed, car runs perfect now.
 
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seb.apprenti

Corporal
Nov 28, 2018
204
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reunion island
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335 i e92
Hello
can you confirm the 3.5b sensor installation procedure?
we unplug the battery, we wait a bit
we replace the sensor, we reverse the wires if we do not buy the BMS harness
We reconnect the battery, we connect to MHD and we tick "sensor 3.5b", we install the MAP and normally there is no problem
Is that it or did I make a mistake?