3.0 engine rattle

[dawesy]

thread revival
mines started doing something like this latly
hard accelaration rev matching on down shifts and more noticeable if cars warmed and ive just parked it like getting fuel always pulling out from the servo will do it 1st and 2nd gear and tonight in 4th at wot did it from 3500 to 4000

same like a exhuast rattle but dont have any heatshields so thinking its pinging but chasing a tacktrix and confirm

did anyone else find a result to theirs

[b120ute]

mine was timing chain tensioner. but only noticeable on idle unlike your symptoms

[libz05]

same here i dont get it on idle!
but between 1500 - 2500 RPM
you can hear it from the engine bay and relaly gets anoying!
not that its loud but its noticeable

[jay.ritchie]

something in my boot has started to make annoying noises.
I think Subaru's are just noisy and annoying

[libz05]

something in my boot has started to make annoying noises.
I think Subaru's are just noisy and annoying

lol
thats not nice

[Tim_]

same here i dont get it on idle!
but between 1500 - 2500 RPM
you can hear it from the engine bay and relaly gets anoying!
not that its loud but its noticeable

I got a mechanic to look at it while my discs were being machined, he said its coming from inside the timing chain cover, so they'll need to take that off to have a better look. He said its nothing to "worry" about, just to get it checked out relatively soon just to be safe.

How did you guys go with this? I have the exact same issue as Libz05 has mentioned. I also noticed Libz05 and Jay.Ritchie (as well as me) have all had a Kido Tune. Have either of you contacted Matt to see wether this is something he can fix? Im not THAT mechanically minded but Matt has told me the following about this issue:

the issue is that going from cruise fuel economy mode to power mode, the variable cam gears have to go from 20 degrees to 50 degrees quite quickly which uses oil pressure to push the gears forward, which means the hydraulic tensioner which normally keeps the chain tight loosens slightly.

Im really hoping this is the issue and its not pinging! Waiting on a reply from Matt (Kido) about when he will be back in my area (or a price to send down the gear to do it remotely). I just really hope its something a re-tune can fix and not hundreds of dollars worth of work.

[jay.ritchie]

I got a mechanic to look at it while my discs were being machined, he said its coming from inside the timing chain cover, so they'll need to take that off to have a better look. He said its nothing to "worry" about, just to get it checked out relatively soon just to be safe.

How did you guys go with this? I have the exact same issue as Libz05 has mentioned. I also noticed Libz05 and Jay.Ritchie (as well as me) have all had a Kido Tune. Have either of you contacted Matt to see wether this is something he can fix? Im not THAT mechanically minded but Matt has told me the following about this issue:

My car was doing this a few weeks before i got it tuned, so it has nothing to do with that...
Its not something a tuner can fix, although im sure he could pull the car apart and replace the tensioner if he wanted too.
Decent job though. Take it to your trusted mechanic, tell them you think its the tensioner and go from there.

And the car has been running flawlessly since its been tuned.
Its a noisy engine, so some quiet rattling when its cold isn't unusual. Nothing compared to what it was like.

[Tim_]

Ahhh ok, well im getting a kido retune in a few weeks and he is pretty confident that he can sus out the issues. My rattle isnt on Idle, only at certain revs in certain gears.
Will update this thread and let you know if the tune sorts it.

[Robbks]

a re-tune could** fix it.

but that's probably only achievable by limiting the cam advance to avoid the drop in oil pressure to the tensioner which will probably make the car even more sluggish down low than they usually are

[KiDo_Tuning]

The best way of looking at it is like riding your first BMX bike, when you went up a hill you had to stand up and use your body weight to apply enough force on the pedals to ride up the hill so you put more tension in the bike chain but when you ride the bike on flat road just cruising at a constant speed, you would sit on the seat and use your thighs. When you wanted to go faster on a flat road, you would stand up again to apply more power to accelerate. Since you are making more power than the factory tune, your equivalent is putting more weight behind the timing chain which is enough to overcome to timing chain tension if oil pressure drops slightly. So a small decrease in initial torque at around 2000rpm to 3000rpm is enough to stop the chain from pushing the hydraulic tensioner back when oil pressure drops at the change over point BUT still having a lot more torque than the sh!thouse factory tune.
Going up a hill or standing up, I think we can all remember the sprockets in the bike making noise

There is definitely no risk of the chain breaking, or the hydraulic tensioner allowing the chain to skip a tooth either

Seen people run flat AVCS in the AVCS A table and/or throw fuel at it to help the transition, not realising that the AVCS A table can be referenced at high load when towing a caravan/boat etc or even with 5 family members on board, which causes a massive loss of towing torque, EGT's to skyrocket, timing being pulled and no improvement in fuel economy or engine torque output.

Nissan SR20 engines had a similar issue with 'rattles' occuring when the hydraulic tensioner could not hold adequate oil pressure

[KiDo_Tuning]

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