Not sure if this is the right section but...

 

Bought the car2 weeks ago now, had a z4 ecu with some strange chip that no one had seen before, the boost gauge in the car was saying i was getting around 8-9 psi, which i belive to be low. car feels pretty quick but only thing I have to compare with is my old TT so not a great comparison that didnt feel as quick and was pushing 14psi. I have just fitted a gems ecu and it is boosting exactly the same however seems quicker.

 

Faulty gauge?

boost leak?

 

 

The vehicle is fitted with a hks fuel cut defender, could this effect it?

 

i knew i should of bought an unmodified car!

On your other post think you said the vac line to the boost gauge was "T" off the map sensor vac line ?

Only thing "T" off the map sensor is the atmospheric pressure sensor , which is not critical as mine isn't even connected.

Might be worth getting rid the t and run direct off thr inlet

Try running 1 direct feed to the map sensor from the inlet manifold (leaving the atmospheric sensor plumbed in if possible)

And another direct vac line from the inlet manifold to the boost gauge .

To See if the boost gauge reads any different

I have found a pipe that isnt connected to anything looks like a boost pipe, it is hanging down on the passenger side. It runs through the front bumper but struggling to see where it goes.

If you're still running tmic don't think they're should be any boost or vacuum lines near front passenger side .

Only things I can think of in that area would be headlight washers (yours shouldn't have them being a jdm)

And the expansion bottle over flow which runs off the yellow cap on the over flow bottle (near the battery) and vents to atmosphere out of the front passenger inner wing .

Chuck a pic or 2 up bud I'll have a look this evening

Cheers savage, the previous owner removed the aircon could it be a pipe for that?

The strange chip that you refer to will be an ESL piggy back chip as the Z4 ecu cannot be remapped, as savage said with the pipes come off the turbo and to the actuator, you need to get in touch with some one that can do live mapping on ESL chips, there are loads of people around, as i would be trying to find out why its making just standard boost and not more especially if someone has gone to the trouble of adding the chip to the board.

also dont compare cars to others cars, get it on the rollers to make sure that its all healthy :)

 

Ash

While checking under the bonnet (pipe is disconected from washers on front bumper) I noticed a blow on the downpipe to turbo gasket, turns out a bolt has snapped turbo side :( could this cause boosting issues?

Yes mate, sorry the aircon pipes do run in that area from near the battery to the bulkhead behind the fuel filter

And yes blowing from the turbo outlet or upipe could cause boosting issues .

the gems ecu is probably not mapped to your spec so I wouldn't drive it too much without getting the map tweeked to suit your car