Help me diagnose this...

[Rush2112]

I've got a 2002 WRX (secondhand) with about 140k miles. Recently (maybe the past two months) I've been having a strange problem.

Basically, when I'm gentle with the gas nothing is wrong. But whenever I put the hammer down (and by that I mean anything from "moderate acceleration" to "pedal to the metal"), I slowly accelerate followed by the engine racing and then falling back into the proper RPMs which is when I get full power. At first, I thought it must be transmission slip, but AFAIK, this would mean NO power to the wheels, and the car DOES accelerate the entire time. So then I thought maybe it was a boost problem, but I can hear it boosting at the appropriate time. So, somehow, some energy is being transferred to the wheels, the engine races (with no power change) the rpms go back down and I've suddenly got full power.

What gives?

[SD_GR]

If it has an automatic transmission suspect the transmission. If it has a manual gearbox suspect the clutch. This is only from the description you've given -- revs climbing then dropping without the car following accordingly.

[Rush2112]

It's a manual, but it only happens under certain circumstances. And I thought I'd lose all power if there was slip?

[Trainrex]

It's a manual, but it only happens under certain circumstances. And I thought I'd lose all power if there was slip?

Nope, you will lose all acceleration when the clutch is finally completely toast. Then you will call for a flatbed. As of right now the clutch is only partially toasted. Full toast will come soon though so start planning for the repair.

[Rush2112]

Nope, you will lose all acceleration when the clutch is finally completely toast. Then you will call for a flatbed. As of right now the clutch is only partially toasted. Full toast will come soon though so start planning for the repair.

After the first reply suggesting the clutch, I started looking around, pricing out what I'd need. According to the "how hard is this to do myself?" thread, I should be able to do it myself, as long as I do it before it gets any colder. So, if I just buy an OEM clutch kit, I won't have to buy or replace anything else, right? Or is this more complicated than that?

[zax]

After the first reply suggesting the clutch, I started looking around, pricing out what I'd need. According to the "how hard is this to do myself?" thread, I should be able to do it myself, as long as I do it before it gets any colder. So, if I just buy an OEM clutch kit, I won't have to buy or replace anything else, right? Or is this more complicated than that?

How good are you with a wrench? Be honest here... what's the most difficult part you've had to install on the car?

[Rush2112]

How good are you with a wrench? Be honest here... what's the most difficult part you've had to install on the car?

I've never done anything to this particular car, but I've always been able to take a set of directions and achieve the desired effect when making a repair. Most difficult? Hell if I know. I'm going to find some tutorials on it before I go ahead and try to do it myself, but financially it's really my only option. Between my limited experience and my dad's vastly superior experience I'm sure it can be done. I just have to find time to drive down to my parents'.

[Pavia]

Honest answer...

I'd give yourself a weekend to do it then. Yes, you can follow instructions, but Murphy can be a *****. Have a buddy available too.

Sure you can do this, it's not rocket science.. (Subie science???)

You will need:

- A garage or flat surface
- Associated support equipment (tools, jack, stands, safety gear, etc.)
- Replacement clutch (Exedy is a good OEM replacement)
- New OEM flywheel
- Throw out bearing
- A good DIY or Tech Manual.
- Clutch fluid. Might as well flush out the old fluid.
- You have to drop the tranny, so maybe you could replace the shifter bushings with Kartboy's

I'm sure I missed something...

[Rush2112]

What's the best way to purchase this stuff? Online would be my guess, but I don't know anything about who would have the best prices and business practice.

[Pavia]

What's the best way to purchase this stuff? Online would be my guess, but I don't know anything about who would have the best prices and business practice.

FastWRX is reputable, but certainly not the only source (but it is on sale):
http://www.fastwrx.com/exsicl.html

OEM flywheel from you local Subaru dealer or SubaruGenuineParts.com and search the OEM catalog.

I would stick with an OEM flywheel for your stock car.

I would not resurface your current flywheel that has 140k on it.

[Rush2112]

FastWRX is reputable, but certainly not the only source (but it is on sale):
http://www.fastwrx.com/exsicl.html

OEM flywheel from you local Subaru dealer or SubaruGenuineParts.com and search the OEM catalog.

I would stick with an OEM flywheel for your stock car.

I would not resurface your current flywheel that has 140k on it.

And you answered my next question which was do I really need to replace the flywheel? But you've got a good point.

[KnightFury]

I would stick with an OEM flywheel for your stock car.

Or upgrade to a lightened flywheel, your there replacing it anyways and imo was a noticeable differense as to response

[zax]

Or upgrade to a lightened flywheel, your there replacing it anyways and imo was a noticeable differense as to response

What Pav is suggesting is a good idea... stick with the OEM flywheel with a stock car. With Bugeyes, lightened flywheels can cause phantom misfire CELs. If the OP is stuck without EM, he has to take it to the shop to clear the codes.

[Pavia]

It wasn't brought up but after 140k miles your car should have been through:

- One timing belt change (plus other belts)
- Two sparkplug changes (if using iridium plugs, more with copper)
- Four coolant flushes
- At least a couple tranny and rear diff change
- Two brake fluid flushs
- One clutch fluid flush
- One power steering fluid flush
- One AC service
- Many engine oil changes

[KnightFury]

What Pav is suggesting is a good idea... stick with the OEM flywheel with a stock car. With Bugeyes, lightened flywheels can cause phantom misfire CELs. If the OP is stuck without EM, he has to take it to the shop to clear the codes.

I have an 03 andhave only experienced awesome things, i have heard of the phantom code if he goes down to say 8lb and yes w/ his applications that would not be wise but a switch to 11-15 would be a noticeable difference, the main reason i did it was when replacing the last bolt on flywheel got stripped beyond all hope so instead of a re-surface i had to grind it off thus needing a replacement so i went lighter and couldnt be happier

Its preference and has to do w/ what th op's goal for the vehicle is but personally it was something that improved for the applications i had and for what i was to do down the road and have accomplised now.

Either way good luck OP