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View Full Version : boost going up , down and up again.



ev3rspeed
08-06-2006, 08:44 AM
I have a question guys.
My car is copletely stock except a 3inch cat back.
My car does this funny thing.
3rd gear, it will boost to about 1.4 bar , go back to 1bar and go back up to 1.3 and drop to 1.1bar by redline.
Is this normal or does it lead to boost leak?

I just checked my lower intercooler pipe last week and found no leaks.

Thanks in advance guys.

KareBearPowa
08-06-2006, 09:08 AM
Evo 9?

myVekDrifteRS
08-06-2006, 09:13 AM
probably needs a reflash or tune.

chuckdashi
08-06-2006, 09:16 AM
that is wierd..... normally i should be going up all the way.... i had almost a similar issue with mine where if i floored it in 4th gear it would stay at 15 pounds of boost.... bu havent had it happen again....

ev3rspeed
08-06-2006, 09:19 AM
Sorry I forgot to mention, it's a evo 9.

Could it be timing being pulled?

KareBearPowa
08-06-2006, 12:04 PM
Did it start as soon as you got the catback? I've been hearing some 9's are more sensitive to airflow changes and the ECU regulates boost to compensate.

SpeedElement
08-06-2006, 02:05 PM
put a hallman mbc on it, if it turns out to be computer related.

smack
08-06-2006, 10:43 PM
it's funny, my car has been doing the same thing since i got it back from the shop.
still bone stock.
i need to do a pressure test just to make sure it all went back together ok. even though
they shouldn't have needed to pull any of the plumbing apart.

AreSTG
08-07-2006, 05:53 AM
my car did this when my EBC wasnt set-up correctly, the solenoid was over-compensating for the speed at which boost raised and would open the wastegate wayy to much. But if the car is literally stock, maybe the computer is jacked and getting a wierd reading, or the stock solenoid is malfunctioning, or your wastegate is malfunctioning.

take it to an ok dealer, exhaust will not make them void your warenty for anything but a cat, and in your case not even that since its cat-back

ev3rspeed
08-07-2006, 09:00 AM
Ima go check the wastegate and see it's tight.
I heard it's a PITA to get to it though.
Any easier way to do this?

AreSTG
08-07-2006, 09:31 AM
dealer, free to get it looked at, if you can get it to do what you are explaining in front of one of them

KareBearPowa
08-07-2006, 10:00 AM
it's funny, my car has been doing the same thing since i got it back from the shop.
still bone stock.
i need to do a pressure test just to make sure it all went back together ok. even though
they shouldn't have needed to pull any of the plumbing apart.



if they pulled the tranny they had to take the intake and upper IC pipes off.

smack
08-07-2006, 10:16 AM
^^^ then i guess i should test it. i was thinking it just came out the bottom.

KareBearPowa
08-07-2006, 10:20 AM
^^^ then i guess i should test it. i was thinking it just came out the bottom.



Battery comes out too. You have to unbolt the upper mounts, all the bolts around the bellhousing that attaches to the block and the shifter cables, etc etc etc etc etc etc

smack
08-07-2006, 10:27 AM
yeah, i just thought that you left the hoses though. and got to everything from the battery opening or underneath.
anyway i'll check it out and make sure it's not just a leak causing the fluctuation in boost.

it's wierd because it's so obvious that i know i would have noticed it if it was doing it before it went in the shop.
i was still breakiing it in for most of the time but i did have a few hundered miles of normal driving that it would have shown up in.

dohcvtec
08-07-2006, 10:36 AM
yeah, i just thought that you left the hoses though. and got to everything from the battery opening or underneath.

its nice to have as much room as possible, especially when you can remove the tubing with just 2 screws and open up that much more space. :)