Hi, 1st of all I'm not to technically minded, so please forgive my stupidity. My problem is I had a few issues with lambda sensor which I have now sorted and found a new problem. After I installed the new sensor I done an ecu reset and noticed during the reset my turbo gauge working nicely, as soon as the reset had finished the gauge stopped working again. There are no fault codes everything seems good. I have noticed that if the car is driven and accelerator held on the gauge builds pressure but if I let my foot off the accelerator it dumps all pressure and stops working. When the engine is first started the needle sits nicely on zero then as soon as I touch the accelerator it drops right down. Basically it seems like I'm dumping pressure unless I have the green and black wires connected to reset ecu. Any help would be much appreciated

 

I may have missed the point. But this sounds normal.

 

Boost gauge only shows boost out on the road.

It will sit near zero, and once you start the engine, you get negative boost, (vacuum), until you are driving hard.

 

No matter how much I push the engine on the open road the boost will start to build but before it even reaches zero if I change gear and let off the accelerator the boost dumps and starts to build but will never actually kick in but if I'm doing an ecu reset the boost and gauge work properly

 

Basically my needle sits on the negative 35 and builds to 30 then dumps out, unless resetting ecu

 

Is this just the gauge or are you getting no boost?
how does the car drive?

 

The car is sluggish, still fast but not what it should be

 

May have knocked a pipe off.
check them all.

Car / model / year / mods may help.

 

It's a subaru impreza 2000 ad 2.0 turbo s reg late 1998, it may be nothing but if I open the car up pedal to floor style it will accelerate nicely then about 4000 to 5000 revs suddenly loses power throwing the driver forward and then accelerates again, when I check under the hood after its blown the bottom pipe off the boost controller, this happens alot, might be nothing but thought it was worth mentioning

 

I had something like this on my old classic... believe it is fuel cut? I would suggest that the gauge/actuator/boost controller piping is all wrong and letting it overboost.

 

Probably right, when I bought the car I noticed a few just dangling around that needed to b put back on, just weird how it's all ok when resetting the ecu