speed.46

hi everyone

the clutch pedel on my impreza is staying down when i but my foot down hard.

any ideas how to fix it.

thanks

danc

check the return spring hasn't popped of ( under the intercooler)

911

Remove the TMIC.
Bleed the slave really well using Dot 5.1 brake fluid. Bleed the slave with the piston pushed and clamped fully IN.

The spring above is a light gauge long spring that is there to stop the clutch fork or arm from rattling with the pull release brg, but it does have a bearing on the situation.

Your plight is a common one with Impreza Turbos.

Have you just had the clutch replaced?

ZEN Performance

The light spring is not to stop the clutch fork from rattling, it's crucial to the proper operation of the clutch. All that is wrong is the spring is missing, the clue is in the fact that it ony happens when accelerating hard through the gears.

Paul

P20SPD

iTrader: (1)

Are you sure about that Paul? Thinking about which way the spring works?

ZEN Performance

Yes I am sure.

The spring keeps the tension on the clutch fork, and allows the clutch slave cylinder to fully extend (it has it's own spring) in between uses of the clutch. When you accelerate hard through the gears, the clutch fork will return only so far as a result of the clutch diaphragm spring, the additional spring takes up any slack. When you next put you foot on the clutch, the fork is already up against the clutch and any extension of the slave cylinder will operate the clutch. Without the spring the slave cylinder doesn't fully extent between uses, and when you press the clutch, you just bring the fork up to the clutch and perhaps disenage it 20% or so.

P20SPD

iTrader: (1)

Ok, cool, good explanation.

speed.46

the spring is there for sure,but i will say one thing i fitted a front mounted intercooler and the bracket it went on we took off and put it on to some other place,but its not like its no where it should be.

so you think bleed the slave and change the oil for 5.1

911

Some years ago I suffered from the pedal sticking down. Usually only on hard accelleration. The 'fork spring' was all there and in the right place.

I bled the slave with 5.1 as I'd had a 'lost' clutch pedal in a very long traffic que in the middle of B'ham and the dealer bled it out with 5.1 and the prob never returned. This was on my UK turbo in 1999.

To my Sti again; the bleeding was not the best of cures and in the end I removed the pedal return assist springs from the top of the clutch pedal after discussing the prob with RCMS. The pedal instantly returned to normal operation even though the posative feel has been reduced. The springs are still on my bench today.

I'm sure the balance point of the system is quite criitical along the way and the pedal may go over-centre and stay down. It usually does not take much to flip it back up with the toe.

As I said above, the spring does have a bearing on the action of the system, but it does not seem that influential in my experience of one car.

During all the efforts to correct the prob I tried a much stronger spring in place of the stock Impreza spec and it made no difference...
All this was 4 years ago, but it was a real problem to solve.

ZEN Performance

Only if the small spring is actually working. if it needs bleeding, the problem will be there all the time, and be worse when the engine bay heats up.

T5NYW

iTrader: (4)

Agree with both 911 and Zen, two valid pionts

IIRC on MY 96-98 there used to be a modded Steel Pipe from Master cylinder to flex which re-routed it further a way from Turbo area??

Tony

911

The entire clutch slave pipework is exposed to the turbo heat, esp when the car is driven slowly in traffic. This is why you bleed the system in high boiling point Dot 5.1 brake fluid.

The bleed may not fix the prob (mine was still in trouble after)

In the end i found one of the 2 location dowels was missing from the engine/box. I must have pushed one through re-fitting my box after a big struggle to get it back on lying on my back with the car on axle stands!
I replaced the dowel on the missing side and all was well!
I think the thrust bearing was binding on the gearbox input shaft housing.

Anyway, it fixed it in the end.