Another knocking engine

I need some help here guys. I have just got my GT from Germany. The car is superb, however just feels a bit "rough" after my V6. Nevermind, its a Subaru anyway, just love it

What's really annoying me is a hardly audible clacking/knocking sound from the left side of the engine. The strangest thing is, that I only here the noise when the engine is warmed up Not audible on cold start...

They have changed the oil 1000 miles before, it is 5W-30 Motul Racing - I am not sure, might be 5W-40, as I did not see the oil container. The car has almost 12.000 miles in it. Temperature should not be a problem, it is around 55 fahrenheit outside.

I guess it should be something with the oil they have put in - because I only hear the noise when the engine is warmed up. I always put octane 95 or higher in the car - sometimes 99

My local dealer did not notice anything strange

What do you think? Should I try another kind of oil? Another type of gasoline?

Which car is this? Is this an EDM car? Or a USDM car that was previously in Europe?

The EDM cars have fairly high compression ratio engines and significantly different timing curves.

Did you datalog this car?

From Germany? Dude, you should've got a BMW. Bimmers are affordable like sunfires in Germany

Well actually, are they??

Not really...actually what you get in the US for $40.000 - eg. the 335i -, it costs at least $55.000 in Germany (or Europe anywhere, it is $60.000 in Hungary). Insane price policy, but that's the case.

You can get it cheaper in the US, than you were living in Germany where they make the car...trust me. I was thinking to IMPORT a BMW from US, because it is cheaper this way. Funny, hmm?

On the other hand I like Subarus better. They are far more better cars than Bimmers.

So back to my Suby, do you guys have any ideas?

Definately a knocking sound, real low-frequency, metallic sound. Can be hear from the inside too. I removed the plastic cover, but it just got louder, so I guess it has nothing to do with the timing belt.

I will make a recording tonight, and post it to you guys. Plase stand-by...thanks!

Unfortunately I did not succeed recording the knocking noise, it is so low frequency, that it is not audible on playback.

BTW one of my friends told me, that I should try a ticker oil, like 15W50 or 20W60. What do you think? I know that the factory oil is 5W30...will the thicker oil harm the engine or any parts of it?

Thicker oil will not harm your engine but it may mask a more serious problem.

It may well be the timing belt tensioner / left hand side. I used to have some oil seeping out from over there. I would take it to a place where they routinely fix WRX and STi cars (be that the dealership or some mechanic). And since you have a USDM car, you need an Accessport. Which not only will it give you more horsepower...but it will allow you to data log and help us diagnose your car more intelligently.

Also with regards to gasoline 95 vs 99...your 95 octane is like our 87 octane. This car is designed to run on premium not on regular fuel. So if you love the car and wanna keep it healthy, for the love of Subaru, put premium in it.

i've had a similar problem.. engine makes loud knocking sound at startup and when it is warm. i can hear it best between 3000-4000 RPMs. a few buddies of mine and myself determined it was a spun rod bearing. i took it to the dealer, they replaced the timing belt tensioner, that did nothing, noise still there. take it back again and the dealer rebuilt the motor, they had my car for 2 weeks. i got it back and i never took the motor over 3500 RPMs for 1000miles. at about 1200 miles, the noise came back. i brought the car back and my dads friend up there is a manager and he had a meeting with me about the Phase 2 EJ-25 engine. he said the pistons are lower friction so that there is a power increase and better fuel economy. since they are lower friction the have a tendency to "slap" -his words, the cylindar walls after there coating wears off, which he told me mine did and that after it does its not bad, however it will make a noise.

when the noice first occured it was at about 37000 miles, i now have 43000 and its still knocking.

my dealer is ******* me over. and i have a feeling my motor will scatter all over the road at 60001 miles. just when the warrenty is up.

Thicker oil will not harm your engine but it may mask a more serious problem.

 

It may well be the timing belt tensioner / left hand side. I used to have some oil seeping out from over there. I would take it to a place where they routinely fix WRX and STi cars (be that the dealership or some mechanic). And since you have a USDM car, you need an Accessport. Which not only will it give you more horsepower...but it will allow you to data log and help us diagnose your car more intelligently.

 

Also with regards to gasoline 95 vs 99...your 95 octane is like our 87 octane. This car is designed to run on premium not on regular fuel. So if you love the car and wanna keep it healthy, for the love of Subaru, put premium in it.

Actually I hear the noise only, when the engine is warmed up. If it were the timing belt, I would hear the noise on startup too...or at least that's what I am thinking Tomorrow my mechanic will have a look at it, just to make it sure.

Back to the octane stuff, yep, thats what I heard from other sources too, so now I am having octane 100 from Shell - can not get better than this. Do you think the poor gas can cause that knocking noise? Maybe I'll try another brand.

I was thinking too of buying an AP from Cobb, it is not cheap, but worth the money - also had been looking for a used one(??). As my GT is a USDM car, nobody has an AP for GTs here in Europe. Its my luck...

Any other suggestions/ideas?

i've had a similar problem.. engine makes loud knocking sound at startup and when it is warm. i can hear it best between 3000-4000 RPMs. a few buddies of mine and myself determined it was a spun rod bearing. i took it to the dealer, they replaced the timing belt tensioner, that did nothing, noise still there. take it back again and the dealer rebuilt the motor, they had my car for 2 weeks. i got it back and i never took the motor over 3500 RPMs for 1000miles. at about 1200 miles, the noise came back. i brought the car back and my dads friend up there is a manager and he had a meeting with me about the Phase 2 EJ-25 engine. he said the pistons are lower friction so that there is a power increase and better fuel economy. since they are lower friction the have a tendency to "slap" -his words, the cylindar walls after there coating wears off, which he told me mine did and that after it does its not bad, however it will make a noise.

when the noice first occured it was at about 37000 miles, i now have 43000 and its still knocking.

 

my dealer is ******* me over. and i have a feeling my motor will scatter all over the road at 60001 miles. just when the warrenty is up.

Actually mine is not so loud, no knocking sound on startup, but when it is warm I can hear it on idle too - I have only 12000 miles in it.

Pfff...so there is no solution but replace the pistons or what??

Rob, I am thinking the same. If it were the pistons, I would hear it right from the startup.

I am thinking of the crankshaft...when the engine oil is thick enough on startup, there is no problem. I suppose the last owner had an oil change and forgot to fill the filter with oil before starting the engine, I guess.

I will try to borrow a professional camera to record the sound for ya to hear it. Or will just park in a sound studio

Back to the octane stuff, yep, thats what I heard from other sources too, so now I am having octane 100 from Shell - can not get better than this. Do you think the poor gas can cause that knocking noise? Maybe I'll try another brand.

If it happens on 100 RON then it's not the fuel and for the record 95 RON is roughly equivilant to the best gas available in California 91 (R+M/2), I'm starting to think this isn't a fuel issue.

It is my second try of half tank gas - 100 RON Shell stuff, and nothing has changed. Unfortunately...damn.

What do you guys think of my crankshaft idea? BTW do anyone has drawing or diagram of the 2005 LGT engine?? EJ255 is the code I guess

Rob, I am thinking the same. If it were the pistons, I would hear it right from the startup.

 

I am thinking of the crankshaft...when the engine oil is thick enough on startup, there is no problem. I suppose the last owner had an oil change and forgot to fill the filter with oil before starting the engine, I guess.

 

I will try to borrow a professional camera to record the sound for ya to hear it. Or will just park in a sound studio

Hi, interesting to hear that somebody else has imported American Subaru to Europe . There are some problems with spare parts ( even shock absorbers differs from EU subaru's ) and competence of local subaru dealers . Not all of them have US-model cartridges to "select monitor".

Your problem is not so called "piston slap", because this noise in Your car appears when engine is warm. Is there any difference when You depressing clutch ? How the noise changes on higher rpm?

Nope, nothing changes when depressing clutch. Noise follows rpm.

It is real funny, but I get the spare parts faster from you guys (from the US), than ordered from the local dealer. Khmmm. No comment...

( even shock absorbers differs from EU subaru's )

You will almost always be better off with Euro Spec over US when it comes to suspension.