overboosting - Perth-WRX.com

[I 86 I] · #1 14-08-2005, 05:11 PM

Hey people

Got a overboosting issue on my MY94
With tee controller is goes to 13psi (which its set for) but spkes to 18psi.
I took controller off and fitted to back to standard and its boosting to 16psi.... and back down to 12psi....... which is normalish
but then it boosts to 18psi and hits fuel cut.

Now, i was using a Tee boost controller and have wound it down to practically shut (which it should make boost to 7psi or around that) and it still boosts to 18psi

Now it wasnt doing this before i :
- fitted new custom air intake and...
- i also took the ecu out and opened it to see if it wash chipped.... which it isnt

- Cleaned AFM (didnt touch it)

Any suggestions?

tuna · #2 14-08-2005, 05:41 PM

plug the turbo wastegate line back in again.

[I 86 I] · #3 14-08-2005, 05:50 PM

Its plugged in

tuna · #4 14-08-2005, 06:35 PM

make sure its not blocked, for a car to over boost its either
a) bad tune
b) really really cold weather
c) boost line disconnected from wastegate, or misplumbed
d) wastegate stuck shut or
e) electronic boost controller fault.

AntonRX · #5 15-08-2005, 08:54 AM

do you mean the stock boost controler is stuff stace?

mat check that line that has the restricter in it maybe its blocked by something and make sure you can blow through it, thats all i could think of last nite everything else is the same as it was before
and maybe when it gets to hi boost the wastegate lines are leaking cause its sorta goes 16 -11 then 18 so maybe it leaks or something

[I 86 I] · #6 15-08-2005, 02:18 PM

Checked all the hoses and lines and no leaks and not blocked.

Car is now also got weird idle (nothing major) and when cruising, say holding pedal on constant 80-100kph, it seems to jerk a bit, almost like its missing.
Could this be from the AFM???
As a AFM for the MY94 is $701.94 from suby, would it be better to go for a new ECU that doesnt use AFM....??

What ECU's do this?

The reason for thinking of new ECU, is that from day one something hasnt been right with it. Never had a smooth boost and always been a bit dodgy. When i put it on speedworks dyno, it was pinging on 17psi with bigger cooler, 98 octane, headers, filter. There was a huge dip in the graph which some ppl thought could be cause of a chip...........but i opened it up and there was no chip in there, altho it had been modified at one stage as one of the small circuits had been re-solderd.

Suggestions?

REXESS · #7 15-08-2005, 02:28 PM

yups sounds like how bruce was about a mth ago

was my AFM, think its the time for the 94-96 ones to die

i was lucky n picked one up cheap from RMS, just call around n see if anyone has em

carls

[I 86 I] · #8 15-08-2005, 02:35 PM

Will do and see how it goes.
Cheers Carls

[I 86 I] · #9 15-08-2005, 09:07 PM

Would a stuffed AFM mess up the boost tho???

REXESS · #10 16-08-2005, 08:58 AM

yuh mine wasnt boosting properly, boost cut n just all over the shop
if yuh want, borrow mine and see if it works, obviously not for long as i need it