[Mudhoney]

Hey All,

I have a 2014 (Aussie 2013) Forester XT. I have noticed that when I put the foot down moderately hard it sometimes gives a nasty noise and there is an accompanying lack of power. The noise is hard to describe, but the first couple of times it sounded like a loose belt or something flapping under the bonnet, but last time it sounded more like it was in the exhaust system. I run 95 RON fuel and the car has been serviced on schedule. Any clues? It does not seem to happen every time.

Thanks,

Mud

 

[dpm]

boost leak or restriction? Any codes?

 

[flstffxe]

How about this to describe the sound?

Marbles rattling around in a can.

If yes, it is likely to be pinging/ignition knock. You could try a higher grade/better brand fuel and see if it subsides.

 

[Spiddelito]

I too have this problem! I have first service and troubleshooting scheduled for Friday. Definently knock/ignition problem, but it doesn't have anything to do with fuel grade. I've had this problem with both 95 and 98 RON, and I can only find one thing that is a constant when it happens. Hard acceleration when engine rpm is lower then 2000rpm AND hard turn right at lower speed. Typically happens when going on a 90 degree on ramp, trying to catch up to traffic speed at highway. I thought I got rid of the problem after a sparkplug failure and change, which had the same knock happen just before the plugg failed.

 

[ASP1135]

I have this exact problem, and so do a few others now. I was first told it was due to my CBE but have had it happen a lot since taking it off.
See http://www.subaruforester.org/vbulletin/f207/cbe-exhaust-causing-issues-244674/

There is also a discussion about it here OzFoz.com • Login

Seems like it is happening more and more. I haven't been able to get Subaru to acknowledge that there is anything wrong yet.

 

[Steve d]

From description given in this thread, I too have had a similar problem.

I've turned over approx 24000km & always run 98RON here in Sydney. I've had my XT since 14 Feb this year, was one of the first to buy from my local dealer.

On the approx 4 occasions that the noise/problem has occurred I was just on or under 2000RPM in Sports mode and attempting to pass a slower vehicle. Flooring the pedal produced a rattling sound (like marbles in exhaust as described above), hesitation, some smoke out of the exhaust then the car accelerated rapidly.

I 've found that if I 'squeeze' the throttle, rather than floor it, all is ok, no noise or hesitation. I've not experienced the problem driving hard in manual mode or sports sharp.

I'm not particularly worried at this stage. Car is due for service in early Feb. I'll mention it then. Hopefully only a software adjustment. Anyhow, will watch this thread with interest. In the meantime might try to replicate the issue and report back to forum and gather some intel for next service.


Steve d

 

[Mudhoney]

it looks like there is some progress on this issue. See the ozfoz thread linked above.

 

[Goshi]

I had a similar issue on my MY09 XT and it was a bad coil causing a misfire (sounded like there was popcorn in the engine, served with harsh hesitation/stuttering, my friend following me thought I was hitting cutoff). Happened when I went over 75% throttle while in boost (so between 2000-5000rpm).

Does the CEL flashes after doing that?

 

[SubieJason]

From description given in this thread, I too have had a similar problem.

I've turned over approx 24000km & always run 98RON here in Sydney. I've had my XT since 14 Feb this year, was one of the first to buy from my local dealer.

On the approx 4 occasions that the noise/problem has occurred I was just on or under 2000RPM in Sports mode and attempting to pass a slower vehicle. Flooring the pedal produced a rattling sound (like marbles in exhaust as described above), hesitation, some smoke out of the exhaust then the car accelerated rapidly.

I 've found that if I 'squeeze' the throttle, rather than floor it, all is ok, no noise or hesitation. I've not experienced the problem driving hard in manual mode or sports sharp.

Steve d

I've had it happen a couple of times in the first week after I first got the car in September 2013. Like you, each time, it was in S-mode and it was below 2000rpm and I floored the accelerator.

I just thought it was my crap driving.

Since then, I almost always drive in S# mode on Manual, and like you, I squeeze the pedal progressively. I drop down a couple of gears / steps to find the right rev range ( at least 2500rpm, preferably > 3000rpm) so there isn't too much boost lag. :rock: Instant gratification.

Hasn't happened since.

After reading this thread, I also took my '14 FXT to a gravel car park and tried the hard take off from a full lock (right, then left) and didn't reproduce the noise we're discussing.

Has it fixed itself ? Here's hoping...

Jason.

 

[ASP1135]

Has it fixed itself ? Here's hoping...

Jason.

I hope so for you but it probably hasn't. I have kept a log of it now since the start of November and have had it happen around 9 times. So roughly once a week or once every 250km. It wont do it for a few weeks and then it do it a couple of times in quick succession.

All I can say is Subaru better get a fix for it soon!

 

[Steve d]

Interesting replies. I was at my Subaru dealer today, picking up son's WRX after a service (he had to work back). Gave the Service Manager a 'heads up' on the issue. Was offered time in the workshop tomorrow, however declined and will wait till next service, due in early Feb.

Service suggested I take their senior tech for a drive to replicate. That's not easy around Sydney suburbs as the issue has been whilst at approx 90 -100KPH and flooring it to overtake. Will have to find a freeway.

Will keep you all posted. As per usual this forum is a wealth of information :icon_biggrin:and will give me plenty of examples to mention to Mr Subaru!

Steve d

 

[Spiddelito]

I had my XT in for service last Friday and I took the mechanic for a ride along to try replicating the hesitation/missfire. And of course couldn't make it happen in the 30min+ that we drove around. But after the shop contacted Subaru Nordic(like SOA), they were told to do a reset and re-learning? of the CVT... Not that they admitted a problem, but that was what they should do anyway. Now after a week and 800km I haven't had the issue happen again. I guess I'll just keep putting my foot down and hope the issue has disappeared...

 

[peruvian]

The problem, or the engine sound happenes on Xt CVT which are Direct Injection engines.... I had a Mitsubishi GDI for many years, I asked many times what the sound was, and finally I was told the followin:

While the engine is coasting, or in saving mode, it runs on a very, very poor mixture ( I was told 40 to 1) and the spark is ultra retarded... when you press the gas to go faster, the engine needs to change from poor to normal to rich mixture... in that process you may hear a knock for a second or two....

In my view, it is drastic change from a 40 to 1, to a normal 16 to 1, to a rich say 10 to 1... (where 40 parts of air for 1 part gas) and the timing advance is also drastic.

Anyway, this is what I was told, and makes sense to me, for the record I never had problems with the car.

 

[Northern AZ Joe]

I was noticing the same noise in my 2014 2.5 Forester with CVT. Had a tech
from Subaru dealer ride with me. He told me that under certain conditions
the chain in the CVT could be heard inside the vehicle. He dismissed detonation
and several other possibilities. Said Subaru had done all it could to quiet the
CVT.....

 

[Bryn88]

Hi guys, I've been following this same problem on here and ozfoz, the guys on there believe that it's a boost leak as 'dpm' mentioned earlier and the knocking sound is from over fueling because the required air pressure/volume has not been matched to the fuel mixture.

Now I have had this problem happen several times now and was quite skeptical of this solution, but willing to try anything at the moment I decided to give it a go!
When the other guys on ozfoz had pulled the engine cover off to tighten everything up they found that the clamps on the TMIC and were so loose it was a joke, so this is where I started and straight away when I went to start tightening up the clamp on the left side of the TMIC you can suddenly see where all that precious boost was going, I done the left side and same thing again loosey goosey!!!

So I started thinking "what if the fittings close to the turbo are loose?" So five minutes later the bash plate under the car was off and found two more clamps the BOV and the turbo air supply and once again both were loose!

Since doing this I drove the car tonight and I am gob smacked!!!! The car is now alive and feels like it has gained 10-20KW easily and no matter how hard I took off in any mode or 'gear' there was and absolutely no loss of power or knocking, the car is as is the car should be!

Honestly anyone who has had this problem or who hasn't experienced it yet tighten up your intake system!

 

[XT-sub]

... So I started thinking "what if the fittings close to the turbo are loose?" So five minutes later the bash plate under the car was off and found two more clamps the BOV and the turbo air supply and once again both were loose! ...

The clamp tightness at the bypass valve I originally posted about on OzFoz.com is important (wasn’t tightened firmly on mine). The one on the air cleaner to turbo air inlet hose won’t cause a boost leak but it could suck in un-filtered air if really loose. Seeing one was loose, it might be worthwhile checking the other clamps on the air cleaner to turbo hose below the air filter box. Although they aren’t in an easy spot to check from the top.

 

[Neveragain]

Has everyone sorted this problem out?

 

[GeoJosh]

Has everyone sorted this problem out?

http://www.subaruforester.org/vbulletin/f207/danoz-fix-fa20dit-turbo-clamps-318129/