Hey guys,

 

Z not behaving as she should. Last I took her out was a couple of weeks ago when she was running perfect boosting great. Then I remember on the way home I gave it some foot and it boosted and straight away I felt a jerk and then I eased my way home. But something did trigger a problem with that jerk I felt. Then today I took her out after a couple of weeks and it wasn't boosting right.

 

Basically, upon putting my foot down, the boost kick in point is fine but it doesn't hold boost and it lags and car kinda gradually gets its speed up. Also when it starts to lose the hold on the boost, I definitely hear a loud whooooshhhh sound coming somewhere from the front of the car. On idle its perfect, not lumpy or anything that says something wrong with the car. I cant hear the whoosh sound when reving in nuetral. Just when driving on boost I can hear it. Also the last bit of boost it holds before whooshing sound, it slightly hesitates as if some boost is going through and then not. Gear changes are funny due to all this too when boosting.

 

I hope I have popped a pipe off somewhere and nothing more. Any ideas where I should be looking??

 

Many thanks.

Check all major pipe couplings for the throttle bodies / intercoolers / turbos, check to see if there are any splits, also on the turbo to intercooler pipes, you have vacuum pipes, might be a good idea to have a nose and check them as well, though ideally you need to make a boost leak checker, someone was making them at some point (check Ebay) basically you remove the maf, using a Air Compressor and a smoke match, you attach your checker to where the MAF goes, light the match first though lol, then pressurise the system to around 18psi and watch for smoke from the match. should help track down any issues, other wise its a case of going over everything by hand.

 

The other thing it could be is the recirc valves if you still have them, could be that the diaphragm has finally given up on one and when hitting boost its just recirculating the boost pressure back into the system

Check all major pipe couplings for the throttle bodies / intercoolers / turbos, check to see if there are any splits, also on the turbo to intercooler pipes, you have vacuum pipes, might be a good idea to have a nose and check them as well, though ideally you need to make a boost leak checker, someone was making them at some point (check Ebay) basically you remove the maf, using a Air Compressor and a smoke match, you attach your checker to where the MAF goes, light the match first though lol, then pressurise the system to around 18psi and watch for smoke from the match. should help track down any issues, other wise its a case of going over everything by hand.

 

The other thing it could be is the recirc valves if you still have them, could be that the diaphragm has finally given up on one and when hitting boost its just recirculating the boost pressure back into the system

 

Many thanks for the that buddy. Will be looking into all that. I do have a boost leak detector somewhere. Normal driving the car is fine. Just on boosting there are issues. And that loud whoosh sound is a give away that air is being lost through somewhere. Boost guage is the standard one and that is reaching slightly less than what it should be. So hopefully it is within reach to get back to 100%. Thanks again. :)

Yup.. All back to normal.. Turns out the intercooler pipe to the passenger turbo was more or less completely off. A little job but as all Z works, a pain to get to. But got there at the end.

pressurise the system to around 18psi

 

Cripes!!