S

Does the issue of piston slap only affect MY98 vehicles or would a MY97 vehicle be affected also???

cheers

S

simon a

i,ve just had a short motor fitted three weeks ago because of piston slap and it is a my97 with 44000 on the clock, as far as i know it can affect most uk imprezas. Try searching for piston slap as there has been quite a few topics on this.

markd

simon a..how bad was the slap. have got same prob but looks like dealer only going to change piston. how did you get new shortmotor ..mark

Karlos

Gents,

are Pre-97 (facelift) models of the impreza affected? I drive a MY96 UK turbo with 110,000 miles on the clock (is that the record) and have just started getting a noise in the morning, which is reminiscent of a Diesel starting up. After about a mile it's fine.....

Karlos

simon a

markd
is your car a turbo?
if so they have to fit a short engine, i think non turboed cars just have a piston replaced, sorry but i don't know why this is

markd

simon a ..who said they have to fit a short engine because my dealer is only going to replace the piston.also rung cheam motors they also only replace no.4 piston.any more help..mark,

Jason L

I think the situation (and i could be wrong!) was that Subaru UK used to fit a new short engine to turbo cars and replace the piston(S) on non-turbo cars.

This appeared to affect late 97 and 98 cars for some reason...

However, it appears now that Subaru have developed a way of just replacing the offending piston (no.3 i believe) on Turbo cars too and so if you acquire piston slap now they will just replace that.

Hope thats helps

Jason

markd

thanks jason...mark

scoobysnacks

Number 3 or number 4 then? Exactly which one is that? I think it's on the passenger side whatever the number.

Jason L

Thought it was number 3.. i could be wrong.. usually the piston just in front of the passenger at the back of the engine bay...

As to the new fix.. spoke to the dealer and apparently they now fit a slightly oversize piston... if thats any help...

RVeiga

I know someone with an MY99 with this. So it appear all of them

AlexM

Erm.... Isn't it a rather bad idea to have one piston bigger than the others?

What about increased weight of the piston /different chamber volumes screwing up the engine balance and smoothness of running?

Sounds like a cheapskate measure to me...

If you're going to fit overbored pistons, then the block should be rebored, and FOUR pistons fitted.

How slight is the overbore on the no. 3?

Hmmm....

Alex.

GrahamF

Anyone got any experience of getting this done out of warranty. I've got a MY98 with 75000 on the clock which has just started rattling. How much does a piston change cost and will Subaru stump up anything outside warranty?

graham

JohnD

iTrader: (5)

I`m beginning to think Subaru`s are made of cheese!
JohnD

AlexM

GrahamF,

I've heard anecdotal evidence that Subaru are pretty generous with goodwill gestures out of warranty where there is a design or manufacturing problem.

My dealer told me of an automatic Justy which blew it's transmission after seven years. Subaru replaced it F.O.C. because there was a known defect in the gearbox which caused the problem..

Certainly can't hurt to try!.

Cheers,

Alex
(slightly worried MY98 owner )

[This message has been edited by AlexM (edited 28 January 2001).]

Spatch

There seems to be alot of threads at the moment about possible piston slap!

I hope this is not a common problem because I thought these engines were pretty bullet proof, if looked after that is???

phill chinn

jason,
do keep us updated, was it still around the £1500 mark,

Jason L

Mark,

Now had the piston fitted and seems at the moment to be working fine.. piston slap noise disappeared but then it did last time to reappear after x 000's of miles... gotta take it easy for 500 miles to bed the piston in so maybe this fix will work better than the short block....

After some concerns expressed on here don't notice any probs at the mo with running 1 piston slightly bigger than the others.. maybe the ECU compensates ???

Jason

markd

jason l..having my98 done under warrenty on thursday thanks for the info..mark

DJB

Mine (MY98 with 36000 miles) goes in for a service on Wednesday night so that it can be checked for piston slap from cold the next day.

I'm not sure what piston slap sounds like but I have noticed that the engine is noisier from cold (particularly frosty days). The noise seems to an accentuation of the normal off-beat boxer sound and is only audible between idle and 2500 revs. When the engine is fully warm, the noise disappears. Performance is not affected and generally the car is running very well.

I'm keen to have the problem (if there is one) resolved before the warranty runs out since I'll have to keep the car for another 2 years.

I'd be interested to know if this is typical of piston slap.

D.

Dick White

DJB, yes it is...you would have possibly have noticed that the noise was more audiable under low revs/high stress ( i.e. reversing out of your driveway ) aswell.

i also found that if i actually lifted the bonnet, and slightly pulled on the throttle linkage, so as to increase the rev`s by a few 100rpm, that i could hear the noise better too.

Dick.
( New short engine fitted, 650 miles on it and still running sweet )

Jason L

Phil,

Both fixes were done under warranty.. so no cost... done 300 miles on the new piston and still taking it easy.. seems to run ok at the mo.. should knock up some more over the weekend so we shall see...

Jason

Harrymattson

If you want to hear piston slap, just fire up any old BDA or BDG!! If you don't know what they are, ask yer dad!

DJB

Car went in for service yesterday and also to have engine noise checked. Service manager has confirmed that there is a problem with "one of the pistons". The dealer has to speak to Subaru UK to get authorisation to carry out repair.

Presumably this means that it is piston slap that is causing the noise. I hope that the repair will mean a new short engine rather than an oversize piston as mentioned above.

I'll keep you posted.

D.

scoobysnacks

Anyone know how much one of these oversized pistons would cost and how difficult it would be to fit one (for a decent mechanic - not me!)? Also, would an oversized piston for a UK Subaru be suitable for a MY98 standard WRX ?

AndyHolmes

Still awaitng the arrival of my new piston...
From the sounds of things they are probably on back order :-(

Of the people who have had this modification done, is there any news on how the engine now performs/sounds ??

Andy Holmes

NITO

I have piston slap and have had from new on my MY98. It only happens first thing in the morning though and disappears after a few minutes. It's embarrasing when people are around but that's about it. The car drives perfectly and is very fast. I really don't see what all the fuss is about. I think I'd rather continue with my engine as it is than have it opened up to have one piston replaced etc. As far as I'm concerned I'll probably run with it until the engine goes kaboom and then go uprated internals anyway.

It's not like the piston slap affects the life of the engine or performance. It worries me that such a big issue is being made of it now, it seems that everyone automatically assumes "I've got an MY98" oh a piston slapper then..you should get it fixed blah blah..."I'm thinking of buying a 98 scoob" make sure the piston slap has been sorted..even the mags have started now, watch out for 97/98 cars with piston slap. Great, so now I have to have my engine pulled apart otherwise a potential buyer will walk away thinking the engine is Fubar'd! When it's simply not the case from what I've heard from many reliable sources! I can't help but feel that it's being blown massively out of proportion.

just my 2p anyway!

Nito

DJB

Nito,

As far as I understand it (spelt out in case I've got it wrong), piston slap occurs because of the free play between the piston and the bore when the engine is cold. This causes the skirt of the piston to hit the bore liner. Presumably as the engine (and oil) heats up the free play lessens and the noise disappears.

Like yours, my MY98 runs very well and always has done. But it has only just started making this noise and it appears to be getting worse every day. With only 6 months of the warranty left, I am keen to have the problem fixed before warranty expires. I will have to keep this present car for at least 2 years and my concern is that eventually bore wear will become worse and ultimately the piston ring/bore seal will be lost. Obviously when this happens the engine will burn oil and performance will suffer.

I am concerned that the current method of fixing the problem involves replacing the offending piston rather than a new short engine. I'm still waiting to hear how they intend to fix my engine.

D.

[This message has been edited by DJB (edited 06 February 2001).]

Jacko

Just a word of warning...I recently had an engine knocking noise on my 97MY at 30K miles. Full dearship service history and meticulously manitained by myself as most of us scooby owners do.
The Knocking noise in question seemed to be emanating from the drivers side, bottom of the engine (piston #4). Noise was worse on cold start and when warm, only audible at lower RPM. One dealership couln't hear a thing, another confirmed Piston Slap.
On further investigation (after about a week) did it turn out that the engine has already had a short motor replacement carried out at about 22K miles to eliminate said Piston slap. Subaru UK therefore, were not going to stump up for a new Short motor, which put me in a rather difficult situation as my car was out of Subaru warranty but still under a dealership warranty.
After great pressure from myself, the dealership in question said they will begin to strip the engine to find out if it is piston slap, with the hope that the dealership warranty would cover once they know that it is mechanical failure.....
It turns out that it was a camshaft pully making the knocking noise and thankfully after my further demonstration of displeasment, was covered under the dealer's warranty! I was without a courtesy car for 2 weeks, as the neither the dealership nor Subaru UK (International Motors) would stump up for the costs. Makes me wonder sometimes whether there is actually any benefit in going to a main dealership at all .
My final peice of advice to give is, PRESSURE THEM 2 HELL TO GET IT DONE (what ever it may be)UNDER WARRANTY! DON'T GIVE UP PUSHING UNTIL YOU'VE SPOKEN (if you have to) TO THE MANAGER AT Subaru UK HIMSELF. WHY SHOULD A CAR SUFFER FROM AN OBVIOUS GENERIC FAILURE SUCH AS THIS AT ALL? ITS DISGUSTING TO AN OTHERWISE WONDEROUS PIECE OF MACHINARY!

NITO

hmm..I see your point DJB..if you've only got a short while left on warranty and its getting worse fair enough. Mine is pretty much the same as it always has been! I never thrash mine from cold..ever, I admit the tappety noise is sometimes a little annoying and as jacko says it shouldn't be there in the first place. I still think I'd rather live with it than risk potential damage by having it rebuilt! It's just worrying that something like this would then affect residuals!

Nito