JohnRoly

Hello all,

I will dive right in with the questions as it is late!!

Was having overboosting problems with my 1995 JDM WRX Wagon, was boosting very strongly upto 1bar and then cutting out and repeating the process up the rev range (especially in 4th and 5th). This was diagnosed as being a leaking wategate actuator and was replaced. Now the car is not boosting anywhere near as strongly, upto about 0.7bar max, and then trailing off to about 0.4-0.5bar at about 6500 rpm. Under heavy acceleration in 5th, seems very low on power and especially boost. Also have a tinny, clanking sound just above idle at low revs (drowned out with high revs I think!!), which I think is the wastegate itself. The sound can be deadned by holding/moving the actuator rod.

Questions are:

What should the standard boost for a 1995 JDM WRX Wagon be?

Surely I shouldn't be getting fading boost? If not, what could be causing this (knackered wastegate??), and is it causing damage?!?!

Why is the car not boosting as strongly and quickly without the leaking wastegate actuator?

Would an ECU reset help the car to understand the change in "breating" in the turbo?

Thanks all, sorry for so many questions, but worried sick!!

Roly

JohnRoly

OK, from doing a bit of research have found out that the 1995 JDM WRX Wagon should run at 0.8bar of boost pressure as standard. Anyone got any ideas why mine is tailing off so rapidly??

Cheers

dj219957

The boost you have now sounds about right. I have a wrx waon with td 04 and before i put on my dawes the figures were simular to yours now. The reason the car feels slower is because you are running stock boost now whereas before because you had a faulty wastegate it was producing more than standard boost until eventually boost was so great that you hit the fuel cut. (the boost probably crept up over time as the problem got worse)
Put a dawes on it with your boost gauge and crank her up the 0.95 bar in 5th and youll love the difference - I use an afr - but you dont need it as the td04 wont produce enough boost before the fuel cut to over lean the mixture - also i dont bother with knock link as i use optimax. Had the dawes on a while with no problems.
i now get 0.95 bar in fith and fourth and 0.7 bar in the other gears.
Andy

dj219957

p.s i dont think the standard boost on jdm wagon is 0.8 bar as it has the td04.

Pavlo

wastegate is too long, the rattle sound is the wastegate 'flapper' rattling. You should be able to shorten the rod a few turns, which will also give you back your boost.

Paul

JohnRoly

Cheers for the advice Andy, am seriously thinking about getting a Dawes device, car just seems so bloooody slow now!! I thought the TT was sluggish, but this is rediculous!!

JohnRoly

P.S., Andy, does your car hold 0.7 all the way up through the rev range, or after the initial surge does it gradually tail off??

JohnRoly

Cheers Pavlo, will go and "fiddle" with it tonight to see what happens!!

dj219957

i get 0.7 in first second third and then 0.95 under load in 4th and 5th - not a massive increase but the spool up is much improved to give a faster feel to the car with very little lag. Cant get any more boost in the lower gears due to the nature of the td04 - may upgrade to td05 if i want more boost.