Problems¡¡ loosing boost

[Rocco]

Hello friends,

i have bad news¡¡

my car does not work like always boosting 2.0bar

Now only can load 1.3/1.4bar.... and i´ve made a boot leak test and all it seems fine,..

the sound inside the car whem the turbo starts to load it is like the noise of a turbine plane... some more than before...because i have installed a cone airfilter and always the noise is hight but now in highter.

i´ve tested my car with and without the DV and it runs bad with both test...and then i think that the DV it is right.

the Vagcom dont says anithing bad......

and an other important thing to say it is that whem the turbo starts to load and i go Under full thorthle during various seconds... i feel like i lose all the power per instant like a fuel cut..... and of course my wideband gauge shows a very bad air/fuel ratio mixture = 16/17..... the bad AFR numbers only comes whem feel the fuel cut just after various seconds under full thortle....because whem the turbo starts to load in the begining the AFR numbers are OK like 12-13... aniway these AFR numbers are bit more bad than before whem my car works perfect = 11/12 in WOT of course not cruising...

WHAT CAN BE??

i am some desesperate
turbo??...it is like NEW...only with 12000kms and always i take care with it
MAF??
Sensors??
ecu??
map??
chips??

and what about the power lost after feel something like fuel cut??

if drive my car like the normal people never have this "feeling" like a fuel cut.... and with "decent" AFR numbers...

sorry for my english,i hope to you can understund me and my problem


PLEASE HELP

thanks ,Tomas

[Pirvu Eugen]

Knock sensors? Maibe?

[Rocco]

Knock sensors? Maibe?

thanks for answer Eugen

knock sensors......i have not a clue¡¡...and if these sensors are bad...the Vagcom dont say nothing??

[Pirvu Eugen]

No. LHDKid from this forum had pretty much the same isue. he changed the WGFV, checked boost leaks, nothing was wrong. He changed the knock sensors and problem solved. Is like the ECU retards ignition advance and reduce boost because reads some knocks. Dont know how to check those sensors except exchange.
All the best!
Eugen

[Rocco]

No. LHDKid from this forum had pretty much the same isue. he changed the WGFV, checked boost leaks, nothing was wrong. He changed the knock sensors and problem solved. Is like the ECU retards ignition advance and reduce boost because reads some knocks. Dont know how to check those sensors except exchange.
All the best!
Eugen

hhmmm.... thanks for explanation it, really dont know the problem of LHDkIDD had


the apart from this... if my knock sensors are good or bad... what about the increment of load noise...if really i am having less boost than before

[Pirvu Eugen]

Maibe the turbo is getting tired. But...just like that? Out off ideas now.
The boost pressure rises at normal level before going down or is not lifting at all?

[Rocco]

Maibe the turbo is getting tired. But...just like that? Out off ideas now.
The boost pressure rises at normal level before going down or is not lifting at all?

My turbo was complete new... and it dont burn or lose engine oil.... my car does not eat nothing of oil...

as you says..now the pressure can´t reach 2.0bar as it did always whe all was Ok.... NOW only can load 1´3 or 1´4 never never more.

thanks Eugen...really i am some desseperate....dont know what to do....

[david]

hi Rocco,sorry to hear your having problem's,hope you get it sorted soon
ecu always cut boost if something seriously not right.

[Rocco]

hi Rocco,sorry to hear your having problem's,hope you get it sorted soon
ecu always cut boost if something seriously not right.

yes cut boost......but the ECU will can cut FUEL too??

[Pirvu Eugen]

Maibe is the WGFV. Electrical ok...but not mechanical. I found some like that, didint show errors but they where malfunctioning.
You can plug the hose from the WGFV to the WG and have a run...expect the fuel cut because off the boost pressure to much....this only iff the ECU has this safety in. But at least you can see iff the boost pressure rises at higher levels like before.
Iff is rising..then is probably the WGFV.
Make the test and let us know!
Regards!
Eugen

[terrybullwon]

The pipe work that your using for you cone filter is
not colapsing?

[Costash]

In my opinion is something like ignition problem and I say check your coil packs before buy new sensors.

[Rocco]

sorry... what it is the WGFV???

i can understund what it is the wastegate valve and the wastegate springs....

i have to say too that i´ve test with 2 wastegate caps and 3 different springs ( 2 normal and the other one stiffer ) and with the harder one i can load around 0´1bar more than with original wastegate spring..aniway the problem it is continue...

ah¡¡ i´ve tested to to "lick" the wastegate cap and my tongue had pasted there

[Rocco]

The pipe work that your using for you cone filter is
not colapsing?

i think that no.... all seems fine..and i´ve tested too 2 kinds of cone airfilters....a green one and an other Pipercross....

[Rocco]

In my opinion is something like ignition problem and I say check your coil packs before buy new sensors.

Ok,,i will do it,but around 6 months ago i had in my hands the distributor,cables,sparks bosch f5dpor like new... and my battery it is NEW,,only 2 months of use



thanks to all for try to help me