knock, knock

Jan 07, 2008 7 Replies

New to this list, and new to Subarus in general, but I've got a question and I'm sure you lads can help....



My '04 Forrester (73k kms) has begun to knock. It became slightly noticible afer my* first or 2nd oil change *(I bought it at 53k kms) and has been growing increasingly louder. Outside temps have been getting increasingly colder at the same time, but nothing lower than -10C. It gets better as it warms up but does not go away completely. It is very similar sounding to the knocking "oval piston" problem that Ford had. Power is good, no blue puffs, mileage is ok (it has been dropping with temp, naturally). I tend to baby this rig and rarely let it see anything beyond 4k rpm and never above



4.5k rpm. Oil is changed every 5k kms (more than recommended by Subaru).

Here's the deal - If it were my old V6 Ford I'd say it was maybe a sticky lifter - but this is a "boxer" and I just don't have any experience with them. I'd like to not appear too stupid when I approach the dealer with this issue so any and all help would be appreciated. The noise is just audible inside under harder acceleration. Has anyone had a similar experience, have any info, educated guesses, or links to sites with information?



I better stop typing so you guys can answer....! Thanks in advance.


"Sandy Hawes" wrote in news:478244f3$0$19893$ snipped-for-privacy@news.aliant.net:

My '03 Impreza developed a very loud knock at cold temperatures and the knock pretty much went away when the vehicle had warmed up. Turned out to be the belt tensioner and was replaced under warranty.

My 01 Outback had that same problem and remedy 5 or 6 times. :-)

It never really goes away in total.

-- Todd H.

2001 Legacy Outback Wagon, 2.5L H-4 Chicago, Illinois USA

Hmm, now that you mention it, when I start out in the morning now with the cold engine (Minnesota) I hear a knock too in my 3 year old Forrester. I guess I mostly have been ignoring it, as it gets better as it warms up (I think.) Maybe I should do something about it. I suppose our warranty is only 3 years, huh? Too late.

Is this something I really need to attend to, or can I just turn up the radio?

My 2005 Forester is making a noise at 4,000 to 4,500 rpm, but I think it is the infamous exhaust heat shield noise. I have 47,000 miles so far.

Blair

Should be covered by the power train warranty.5 years or 60,000 miles.

Blair

Some subies have piston slap, a knock like sound that has no cure (according to the subaru gods). Not sure what engines it covers. couldent find anything on yours, but found this:

02-93-04 tsb covers a knocking noise due to timing belt tensioner bracket (Vin's and porduction dates apply)

Thanks Steve. Good info. I'm hoping its the tensioner.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required