Boost Leak - Tried Everything :(

[Saaamon]

If your seeing 20psi and holding 18 it sounds like everything is good. You won't hold boost on part throttle.

If you're still in doubt get a pressurised smoke test. Only 30 odd quid and will find the smallest of leaks.

Already told him that at the start of the thread but as per usual people would rather change a load of serviceable parts than spend money on actually diagnosing a problem properly.

[WillT5]

Thanks very much for your replies Mitchey and T5G

Im worried that the boost isn't building quickly enough and feel that it must be leaking due to not holding in second. I will try and phone some different garages but had already tried calling tuning companies around me but everyone treats me like im speaking Japanese, think i must be living in the wrong area or just need to some contacts

I will post back when i have the problem resolved for anyone else struggling

Will,

[JamesT5]

Engine Smoke/Leak Test. I had one done on my T5 the other week and to be fair the guy who did it was an absolute Gem and even spent a couple of hours fiddling about trying to fix them for me.

[WillT5]

Does anybody have any contact numbers for a garage that will do smoke testing? Im in Surrey

Thanks,

Will,

[mitchyboy01]

Thanks very much for your replies Mitchey and T5G

Im worried that the boost isn't building quickly enough and feel that it must be leaking due to not holding in second. I will try and phone some different garages but had already tried calling tuning companies around me but everyone treats me like im speaking Japanese, think i must be living in the wrong area or just need to some contacts

I will post back when i have the problem resolved for anyone else struggling

Will,

Boost won't hold in second as there isn't enough load. From what I've read so far your car sounds normal.

[claymore]

Sounds to me as if you're looking for a problem that isn't there.

[WillT5]

Have spent the day testing on country roads and motorways. Boost goes down rapidly in second gear and bottoms at 10 psi, third is a bit hit and miss. It sometimes holds at 16-18 psi but when i stamp on it, it will drop to 10-13 psi

Ive replaced the vacuum tree o ring but same result, have also tested with MBC to rule TCV out

My last car i ran at 27 psi so have had experience of boost leaks, im sure its the same issue

[JamesT5]

Sounds to me as if you're looking for a problem that isn't there.

I think there is a problem judging by the symptoms. Better to check and make sure, I always say "follow your instincts".

[claymore]

Boost is dictated by load, there will be very little load in second gear so it won't hold it unless you're going up a very long, steep hill. my car will boost to 22psi then drop back to 18psi as the revs go up.

EDIT: Just noticed that you have a dump valve, is it twin piston?

[WillT5]

Thanks James, still trying to find a garage that will smoke test it for me. I would ask for the contact number for yours but wales is a bit out the way for me

Thanks Claymore, Its a bailey single piston i believe but i have ruled this out also. Ran without a BOV or Ricirc for a while and no change, may test it again though

[theflyingbrick]

ahhh the old dump valve problems lol as claymore said,if its a single piston dv then throw it away as itll leak!! quick test would be take the vacuum pipe off the top of it tie it in a knot or cap it off and go for a drive see if its any different also have you fitted a blanking plate on the turbo?

[WillT5]

Thanks guys, i will go and test this now (off ooout). Unsure if its twin or single as i cant find anything definitive, found a picture of the same BOV:




Unfortunately cant see the model written on it

Will,

Edit: Sorry, yes i have fitted a blanking plate. TIGHT just in case. Have tried a plate cut to size with silicone sealant and now im using one with O Rings

[foammanmark]

Thanks James, still trying to find a garage that will smoke test it for me. I would ask for the contact number for yours but wales is a bit out the way for me

Thanks Claymore, Its a bailey single piston i believe but i have ruled this out also. Ran without a BOV or Ricirc for a while and no change, may test it again though

GRN smoke tested my V70 R prior to fitting the mapped ecu.

[WillT5]

Unfortunately that didn't work, boost just pushed open the bov. It Definately makes it worse if I stamp in the pedal rather then build boost slowly

[claymore]

Unfortunately that didn't work, boost just pushed open the bov. It Definately makes it worse if I stamp in the pedal rather then build boost slowly

Of course it did, it relies on boost from the vac pipe to keep it closed, take the dump valve off and blank the pipe.

[WillT5]

Was asked to try this above. I have blocked it off previously with no effect

[oblark]

Hi Guys,

Ive got a boost leak somewhere on my Volvo 850, its got a Rica 304 but ive never seen 17 psi! In second gear i get 14 psi spike which rapidly drops to 10 psi and holds and in 3rd, 4th and 5th it sits at a constant 14/15 psi

Ive got a DIY Rip kit with T bolt clamps on every join all extremely tight, i have a o-ring sealed turbo blanking plate, i have replaced the PCV system and put clamps on every pipe joined to the manifold. Also tested the BOV and TCS which are both fine

Would really appreciate any advice

Will,

Above are the engine load setpoints at WOT from one of my maps, as you can see high revs with a greater throttle opening the high the load.which means more boost.

If all the values from 3000 rpm and 20% throttle opening where set to 10 ( max is 10 ) them it would boost like ££££ and you would end with this,



From what I`ve seen of the rica map your map is doing what it surposed to do.

[claymore]

Above are the engine load setpoints at WOT from one of my maps, as you can see high revs with a greater throttle opening the high the load.which means more boost.

If all the values from 3000 rpm and 20% throttle opening where set to 10 ( max is 10 ) them it would boost like ££££ and you would end with this,



From what I`ve seen of the rica map your map is doing what it surposed to do.

As I said earlier, chasing a problem that isn't there.

[WillT5]

If this was the case would i see the boost gauge slowly descending with my throttle at 100%. Would it not hit a set limit (17psi i believe for the RICA) and stick to it?

I understand that tuned ecu's dont give you full boost until around 4000 RPM to protect the rods but the boost drops below 15 psi all the way to redline

[T5frankie]

If this was the case would i see the boost gauge slowly descending with my throttle at 100%. Would it not hit a set limit (17psi i believe for the RICA) and stick to it?

I understand that tuned ecu's dont give you full boost until around 4000 RPM to protect the rods but the boost drops below 15 psi all the way to redline

in every gear you will get peak boost then it will drop as the revs climb, you'll need a forge actuator to keep it at peak boost