fuel cut at full boost...? why?

[prj]

Look for boost leak first.
Also if boost has been raised above what the software is made for using mechanical means or a separate boost controller, you can get the same issue.

[rs200]

before few years on my car was fuel cut too , but the problem was N75 valve..

in his case N75 is good. so we can go to look for boost leak or MAF problem ?

thanks Dmitri

[prj]

Boost leak.

Fuel cut is simply MAF based. If MAF reading exceeds XX at a certain RPM -> Fuel cut.
(this is simplified, it's actually a load limiter...)

But generally yes, this limiter is there so you don't max out your injectors, causing lean mixture and detonation.

[rs200]

my friend have a problem with fuel cut at full boost ... 1.4 bar.. s4 (aan)

why did Motronic do that? to save the engine from over boost and lean mixture?

can somebody explain that to me?

thanks..

Igor