What is needed to run with VEMS?

[a4kquattro]

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?

Hi Jamo,

without drilling the hole larger, you need to grind down the diameter of the stock sensor, like so. Using a lathe to do this would be nice, but chucking it in would be difficult..

Honestly, I'd just recommend drilling the hole larger in the manifold. it makes for a cleaner install.

[a4kquattro]

and to be clear this is not "needed to run vems", just something to improve the IAT accuracy over the stock PTC sensor if so desired.

[Jonas_R]

Should there be any problem installing this sensor in the pipe just before the throttle body?

[a4kquattro]

Should there be any problem installing this sensor in the pipe just before the throttle body?

that will work "ok", in the manifold is better but part throttle and closed throttle IAT will not be as accurate.

[Error404]

sorry to hijack - will that intake temp sensor work with motronic?

[a4kquattro]

sorry to hijack - will that intake temp sensor work with motronic?

no. The 1.8t sensor is NTC or "negative temperature coefficient". Stock AAN/ABY/etc air temp sensor is PTC or "positive temperature coefficient". Not compatible. VEMS can cope because it is possible to alter the hardware and update the calibration curve to fit whatever sensor you want to run..

[max_s2]

IMHO the easiest way is to cut resistor from the old "house" (stock 20vt PTC's one) and solidaire the 1.8T resistor (NTC one) in it. No drilling or plastic cutting or else what, just a nice solidaire and you're done

[Bram]

What do I need to change in the VEMS hardware in order to make use of this new sensor?

[Jonas_R]

Marc:

What is the VR pin adaptor you mention on your site?

[Jamo]

Marc:

What is the VR pin adaptor you mention on your site?

When you run VEMS you have to swap the pins on the VR Plug.

Marc has an adapter to the plug so you don't have to do this.

However I heard this could be changed in the VEMS software without having to change the plug, I can't comment if this is true or not though

[GazzaG60]

this isn't done in software. the polarity change is needed. the good thing is motronic will still run with it changed if need be.

the other change was that the wiring for the vems PNP is for aan and not aby. its an ignition wire that can either be swapped or done in software.

the only change needed to run vems is the polarity. then you have the option of the temp sensor. i know that peter uses a different sensor again to that. must say ive seen no real issue with mine but it must be there. i believe its the poorer IC'd cars that suffer most.

[a4kquattro]

What do I need to change in the VEMS hardware in order to make use of this new sensor?

there is a "piggybacked" resistor inside the ecu that needs to be removed. once the resistor is removed you need to re-upload your firmware with the appropriate temperature curve for the 1.8t sensor. I can help you with all that when you are ready.

[Jonas_R]

Marc: Can I buy that adaptor cable from you?

[a4kquattro]

Marc: Can I buy that adaptor cable from you?

Sure, email me

[Bram]

The main problem for me is to drill a bigger hole in the IM, since it's attached already on the the cyl head. I can not find a way to make sure there are no left overs of the drilling metal on the inside of the IM, so it's a bit too risky for now.

How do you normally drill that bigger hole in the IM and what precautions should I take?