Hey guys. The link above shows my zed at 0.9 bar of boost... However you can see that the boost needle waves from 1 bar to 0.8. The car also feels like... fast then slower then fast then slower again.

At stock boost with the ebc off there is no problem. Currently ran at 0.6 bar on way home and didn't see a problem but it might be because I couldn't use boost much :)

what could this be?

Fault with boost controller?

Vacuum leak?

Open to answers :D

try the cheapest, easiest things first...

 

full PM(clean) on connectors, then a vac test.. so many things ... ecu temp sender .. CAS .. blah..blah

 

the boost fluctuation "may" be down to a running issue and not vacuum or the controller..

Already changed and cleaned a lot of the sensors. The only ones I haven't changed or cleaned are the ones right at the back of the plenum where the idle control is.

 

Also. Best way to do vacuum test?

Found a leak not too long ago. Sorted now much better but not perfect

Might also be a good point that my fmic has a large dint in it... and I mean. Large. Isn't loosing any air but the air flow will not be straight through. It will bend round...

having a dent in the FMC even a large one wont cause the symptoms you are having . you are going on and off boost and loosing nearly 3 psi of boost peak to peak....check the boost lines that they are not restricted ..check your connections that they are not crimping the boost lines , check the boost solenoid is stable and not lifting off , check the earth to the EBC all these things can give you wierd symptoms

 

cheers and good luck

 

steve

Thankyou Steve will have a good look :)

More information required:

 

EBC model?

EBC settings?

as far as boost leak test, just make yourself a plug... I've made a few in the past... e.g.

 

 

i wouldn't bother with the smoke matches... a waste of time really...

 

Update on the situation :). Sorted it. Some of the boost pipes wernt supported so at high boost they just opened at the ends. All done now and a nice stable boost :D