2003 1.8t, i need small favour please

[Darran]

Ok fellow frustated 1.8t owners,i need to know which way round 2 plugs go.

If you look under the inlet manifold from n/s you will see 2 sensors bolted on the underside with vac pipes running into them , 1 has a green plug ,1 has a brown plug, which plug is nearest tothe front of the car please?

Many thanks.

 

[QuattroCalum]

Brown connector goes to N249 solenoid nearest the front of the car. I'm sure the solenoids are colour coded with the wiring connectors but I disconnected mine just to make sure.

 

[Darran]

Thnx Calum. ****** its made thing's worse!

Gettin bored of fixin these thing's with overboost faults!!!!!

 

[QuattroCalum]

Thnx Calum. ****** its made thing's worse!

Gettin bored of fixin these thing's with overboost faults!!!!!

How are you getting overboost on standard map? What's the fault code you're getting.

 

[Darran]

You can get overboost on any map if n75 or wastegate is faulty, not my vehicle its a customer but its a very common fault on the 1.8t, gonna fit a mbc and go from there its easiest way to find the fault vcds is ok but its not fool proof.

Cant remember the fault code but it was overboost, i then fit my boost gauge and check and sure enough its boosting up towards 30psi momentarily until soft limp kicks in,1.8t,s suffer terribly with this fault ,its a **** system to be honest.

 

[Darran]

Poxy n75 ,it would seem that vcds is struggling to detect this, ive had over 10 of these in and its always been n75 yet the valve switches when tested, it would seem the parameters set in vcds must be to far apart?Hence vcds does not show fault or maybe audis obd program is wrong and doesn't pick it up.

On the brightside you can squeeze another 2psi boost using mbc giving a steady maintained boost of 10 psi at wot instead of the 8psi if your lucky, standard boost.

 

[QuattroCalum]

Poxy n75 ,it would seem that vcds is struggling to detect this, ive had over 10 of these in and its always been n75 yet the valve switches when tested, it would seem the parameters set in vcds must be to far apart?Hence vcds does not show fault or maybe audis obd program is wrong and doesn't pick it up.

On the brightside you can squeeze another 2psi boost using mbc giving a steady maintained boost of 10 psi at wot instead of the 8psi if your lucky, standard boost.

Interesting, how would you fit MBC I've dabbled with one of them before but it was frustrating, it wouldn't work properly.

 

[Darran]

The main reason they dont work is because ppl fit the mbc in the car then run pipes to actuator/turbo port and intake pipe,the pipes are way to long if you do this and the result is very little manual control,the trick is to fit the mbc under the bonnet, i fit them to the original pipes securing the controller to the intake pipe with a zip tie. Its takes a few runs to set them up but you will need a boost gauge in the car to monitor the boost,if you go beyond 22psi the ecu will dump the excess through the recirc valve and go into soft limp but to be honest its best not to go over 10psi constant on wot in 4th gear,if you want more power get it mapped.

I start by hardly opening the mbc roughly half a turn from closed then open it tiny increments at a time.

Oh yeah MOST IMPORTANTLY leave the original n75 connected just took it out the way, by connected i mean leave it plugged in electrically!

 

[QuattroCalum]

The main reason they dont work is because ppl fit the mbc in the car then run pipes to actuator/turbo port and intake pipe,the pipes are way to long if you do this and the result is very little manual control,the trick is to fit the mbc under the bonnet, i fit them to the original pipes securing the controller to the intake pipe with a zip tie. Its takes a few runs to set them up but you will need a boost gauge in the car to monitor the boost,if you go beyond 22psi the ecu will dump the excess through the recirc valve and go into soft limp but to be honest its best not to go over 10psi constant on wot in 4th gear,if you want more power get it mapped.

I start by hardly opening the mbc roughly half a turn from closed then open it tiny increments at a time.

Oh yeah MOST IMPORTANTLY leave the original n75 connected just took it out the way, by connected i mean leave it plugged in electrically!

Thanks for your advice Darran.