What is needed to run with VEMS?

[GazzaG60]

there are known issues as marc says with the temp sensor. there is an updated file that can be used on vems to help. i use the standard file and sensor and have no issues. i may try the newer version just to see how it is but im still in lazy mode at the moment

[Jamo]

the stock (PTC) air temp sensor's reading is somewhat 'aliased', meaning that it will jump in increments of about 8C. The 1.8t style sensor is smoother and more linear, I generally recommend going with the NTC sensor for applications over 400hp.

Would that sensor work with stock motronics?

[GazzaG60]

not sure jamo. id expect the calibration table in motronic would need changing. sure paul can help here. no reason why not

[Rocco]

advantages over motronic are:

1) ability to change maps at will. This is important if you intend on mixing and matching parts (turbo, injectors, etc)
2) removal of the MAF = improved breathing
3) onboard wideband support for better fuel control both on-boost and off.
4) onboard egt
5) launch control

hmm.. it seems 99% plugg/play if buy the Vems for 3B engines.....

i have installed a wideband sensor and gauge but of course it is not conected to the ECU..only for wacht the gauge of the AFR...with Vems will be better sure


thanks for the explanation

[dkw_dude]

Thanks for the replies. Think I'll use the standard IAT for a start, my hp goals are around 350 (RS2 hardware installed with chip from another S2 with ~same setup). Will go for E85 later.

[Jonas_R]

People mention EGT and Wideband sensor.
I get that the Wideband sensor is needed for the ECU, but what about the EGT sensor? I mean I'm already running a EGT sensor, Wideband, etc from Zeitronix and have a nice system that I really dont want to change.

Also where do you gues have the Wideband sensor located? Is stock lambda location ok?
The plan was to use my Zeitronix Wideband sensor for tuning.

[Jonas_R]

So this is my order list at the moment:

1x VEMS Motronic55 for AAN/ABU/ADU
Order lines:
"weak (2k7) MAT pullup for NTC MAT"

1x Wideband sensor

1x MAT sensor (standard VAG item) 038 906 051 - I think I could get this with a matching plug from my local audi dealer.

1x Diode which I can get from Marc?

[A80Avant]

yes you can.

mind though that if you go with the 1.8T MAT sensor, you will have to modify the insert on the inlet manifold with a dremmel,and probably wont be able to fit the motronic sensor back in sufficiently to avoid any boost leaks. You would probably have to open a second hole for that if you wish to go back to motronic.

I must admit, the 1.8T sensor is a better item to use and cheaper if it breaks down. BUT having said that, with version 1.1.27 that is quite usefull. On version 1.1.56 which VEMS told me are thinking of making it the official update on the firmware, you will have the possibility to adjust ignition timing with MAT retard/advance on your own temperatures. Therefore, if you have lots of logs with your temp. variables depending on your intercooler, you could set the values you need even with the old MAT sensor. Motronic has that ability and i doubt that you would need to make so small changes in the future to get even a 1-2C difference to take advantage of.

In my car i usually see temps on casual driving about 5-10C above ambient most of the times and after lots of runs,it goes up when stationary. Water injection brings that down instantly when used and gets rid of the heatsoak but overall on those semi hot days i have done most of my runs here (20-25C) i can get the MAT temp,down to 19C even when the ambient temp is 24C with water injection.I doubt that i would have much difference if i had used the 1.8T sensor.

Having said that, the 1.8T sensor is much much cheaper!!!

[A80Avant]

By the way,
make sure you get the 1.1.27 version and megatune 1.1.27beta6 for now. Also ask for the highboost(400kpa) map sensor in the ecu and get them to load it up with 16x14 maps.Much more efficient than the 12x12 and newer firmwares will only use 16x14 maps

[Jonas_R]

So just to sum up:

1. I don't need EGT probe and placeing wideband in stock location = OK

2. Changing the inlet on the manifold, I dont like that. Would prefer to be able to go back to stock.
2a. Do you know what it involves? "weak (2k7) MAT pullup for NTC MAT" Was thinking that I could always change later on?

3. On the VEMS page it says that it comes with the 400KPa Map sensor unless otherwise specified.
3a. Will note that with the 16x14 map.

[A80Avant]

if you just want to keep the excisting MAT sensor, then just let Marc know or whoever you are ordering the ecu from.

i talked to marc about this and as i wanted to be able to do the same thing i left the OEM MAT sensor there,and in the future there is one resistor to take out from VEMS to make the 1.8T work

[Jonas_R]

Good to know, then I think I will order it so I can use the original MAT sensor.

Already ordered the NTC type MAT sensor from audi, so will have a look at in and what needs to be done to fit.

[A80Avant]

ok

give us some feedback with photos as well!!
thats the vems spirit!haha

[s2martyn]

sorry to hijack but i need a few answers.as i am on the verge of scrapping the bosch motronic..
does this ecu plug straight in with no wiring mods?
also can you get rid of the maf?
is the software relativly easy to use to map the car?
do i need just the ecu?
thanks martyn

[Jamo]

the stock (PTC) air temp sensor's reading is somewhat 'aliased', meaning that it will jump in increments of about 8C. The 1.8t style sensor is smoother and more linear, I generally recommend going with the NTC sensor for applications over 400hp.

I believe you found a way to install the 1.8t sensor in the stock sensor position but I cant find the details on motorgeeks, could you post here please?

Also where is actually the best position for the sensor?