tacho and boost problems.

For the older twin turbo B4 models

tacho and boost problems.

Postby RIBROD » Fri Jan 16, 2015 3:10 pm

Hey guys i am new to subarus and i have had a problem with my 2nd turbo kicking it at 5000 rpm, im lead to believe its meant to kick in at 4-4500 rpm. Also i can now here it building up boost and going to waste wich when i bought the car you wouldnt know it had turbos.

Also a new problem has started where randomly between 2-4000rpm the tacho will jump up 100rpm then drop back down i can here the turbo spool and engine rev but car doesnt go faster, it all happens in like 5 seconds. I feel it could be the clutch slipping because of hot spots on the plates.

I dont know if it is all related to each other. Any help would be appreciated.
RIBROD
 
Posts: 4
Joined: Fri Jan 16, 2015 2:52 pm
Car: 01 liberty b4
Real name: Benji

Re: tacho and boost problems.

Postby sparrow » Fri Jan 16, 2015 7:49 pm

so your secondary kicks in at 5000-1000 later than it ''should'' but it does still however kick in?
and you can hear a boost leak after 4000?
and you have no primary turbo?
i dont think you should be hearing a large amount of primary spool, the turbos are tiny.
take it to a mechanic that knows turbos and tell them you suspect you have a boost leak.
sparrow
 
Posts: 63
Joined: Tue Dec 10, 2013 7:50 pm
Location: central coast nsw
Car: b4

Re: tacho and boost problems.

Postby nickknack » Mon Jan 19, 2015 2:48 pm

That depends, I have a cai and the turbo spool, even on primary, is much louder. Sorry I don't have any advice OP but to find someone who is experienced with the TT system.. Many mechanics will just be confused by it.
User avatar
nickknack
 
Posts: 155
Joined: Tue Apr 17, 2012 3:01 pm
Location: Canberra
Car: Black MY02 Liberty B4
Real name: Nick
Profile URL: viewtopic.php?f=7&t=16448

Re: tacho and boost problems.

Postby RIBROD » Mon Jan 19, 2015 5:27 pm

I think the 2nd turbo is meant to engage at 4000-4500 rpm but is kicking in at 5000 rpm.
I do have a primary turbo and i can here that building pressure when i get over 2500 rpm as as well as the second one when it kicks in.
i have had it leak tested and dynod, they said it isnt leaking but is down on power but they didnt know why and it could take a while to find out why its down.
i also have a feeling the clutch is slipping while fully engaged.
RIBROD
 
Posts: 4
Joined: Fri Jan 16, 2015 2:52 pm
Car: 01 liberty b4
Real name: Benji

Re: tacho and boost problems.

Postby sparrow » Tue Jan 20, 2015 4:27 pm

could be any section of the secondary switch over, you hear it building but its being lost somewhere.
icv-egcv-secondary bov.

this is where i'd start.
ecgv is a big job. other two arent to painful.
i can sell you both a secondary bov and an icv if you want to start eliminating causes for cheap.
60 shipped for both or 30 each.
sparrow
 
Posts: 63
Joined: Tue Dec 10, 2013 7:50 pm
Location: central coast nsw
Car: b4

Re: tacho and boost problems.

Postby RIBROD » Thu Jan 29, 2015 3:16 pm

Okay thanks mate ill keep that in mind may grab them off you eventually if you still have them. At the moment im looking at the Valve assembly intake control.
RIBROD
 
Posts: 4
Joined: Fri Jan 16, 2015 2:52 pm
Car: 01 liberty b4
Real name: Benji

Re: tacho and boost problems.

Postby Robbks » Thu Jan 29, 2015 3:30 pm

mate do some proper testing.
have someone else drive the car on a nice bit of slightly uphill highway
use 4th gear, crawl along at 1500rpm

watch your boost gauge and tacho
have them push the throttle wide open and watch and listen
at around 4000rpm you should hear teh exhaust and intake not chage
and the boost begin to drop a few psi at about 4200rpm,
you should next (about 4500rpm) hear the exhaust note change, then the intercooler valve open with a sshhhooonk sound
Still watching the boost, it will begin to build again, and yet it might be 5000rpm before it reaches 15psi again

by this time you're probably at the speed limit.

if it's different to above, then let us know.
you're in for some more homework and time checking things

if it's serious, forget about changing valves and stuffing with it
rip it all out, convert to single.
coyote wrote:Sure, a GTR is fast ... but it's about as interesting as listening to grass grow.
User avatar
Robbks
 
Posts: 2185
Joined: Wed Jan 05, 2011 8:21 am
Location: Hobart, Tas
Car: MY06 3.0RB Wagon
Real name: Rob
Profile URL: viewtopic.php?f=10&t=12350


Return to B4 Specific

Who is online

Users browsing this forum: No registered users and 2 guests