Power delivery not smooth when cold

[glion]

When the car is cold the power delivery doesn't seem to be very smooth. It only takes about 30 seconds and then it back to normal. This only happens in the morning as the car has been sitting overnight. If I go to the shops for an hour I think the engine must retain a little heat and it runs fine.

Its like the power comes and goes a bit, could be described as a surge in power then its back.

What would a likely cause of this be? Hasn't been serviced in ~17,000Km I've changed the engine and box oil though.

2011 JDM 2.0L Turbo Sti.

[Guest]

Do you let it warm up before driving it?

[Andy_Mac]

Sounds just like the problem that plagued 3rd gen legacy's

[glion]

 evowrx said:

Do you let it warm up before driving it?

No, I just hop in and I'm off.

[94 Leone]

 Andy_Mac said:

Sounds just like the problem that plagued 3rd gen legacy's

poor maintenance?

[Andy_Mac]

Not basic maintenance atleast. Afm was always the first suggestion and sometimes fixes it but other times not. Marky had it back in the day and ended up changing pretty much everything replaceable to get rid of it i believe.

Are you taking it easy or driving pretty aggressive when this happens?

[WRXER]

 glion said:

No, I just hop in and I'm off.

There is your problem

[Guest]

Let it warm for 30-60 sec then try it.

[glion]

 evowrx said:

Let it warm for 30-60 sec then try it.

Yes, if i let it warm up then there is no issue. Is this a standard Subaru issue?

Its subtle and its not really a big issue, its just that it could be better. If it was something like bad plugs, or easy to fix then i'm keen to fix it.

If the RPM is kept high over 2500/3000 then it doesn't really show.

[Guest]

New car issue well 98- with subaru.

[Joker]

good info

[Kiwi_Fozze]

Ok issues are:

17000km with no service. Recomended service interval with the grb's is 7500km, with 5w30

asking for power when cold. Shouldnt be giving it any boot until oil temp is up over 70 degrees. Usually takes about 10-15 mins of gentle driving after water is up to temp.

3: electronic throttle can be a little jerky on these. Think of it as a feture. Less noticable when in than in or [s#]

[Guest]

Had oil change just not service. Oil can go twice that safely but testing wouldnt hurt the first time.

[Kiwi_Fozze]

Oil is cheeper than an engine

[Guest]

Thats stoopid burn money for fun reasoning. If your full syn oil is fckd by 7500km you have severe issues and changing oil wont help you. Timing belts are cheaper than engines but i wont replace mine every 20000km.

[Kiwi_Fozze]

Piece of mind. If your oil filter is clogged to the point of having shards of steel floating around in the oil... just my opinion, but for my piece of mind i do it every 5000 - 7500 km. With filter.

[glion]

i just stubbed across this blog post.... of someone in NZ, maybe a member.

http://sergei.nz/grb-sti-tgv-deletion/

 

One thing I noticed: since removal (even before tune) the “hole” around 3000rpm during warm-up has disappeared.

Sounds like that might be what i'm experiencing.

[Guest]

Im being a dick but if you have steel in your oil and its a subaru you will be hearing funny noises long before you change your oil. Same goes for the filter only warning you will get is a man with a hammer. If filter clogs - which they dont can even last 40000km dependant on many things - they will bypass which sends dirty unfiltered oil thro engine. Oil itself breaks down contaminants smaller than the filter micron rating and carries it. Once oil cant carry any more **** its spent same goes if it cooks etc etc. Anything big oil additives cant break down is caught in filter.

I would change at 10000km max i was just pointing out oil wouldnt cause that issue. Ive got customers with same oil in dirty diesels running 25000km and testing fine.

Tldr: oil wouldnt cause op issue.

[boon]

Worth asking, what sort of fuel are you running it on?

Also it could be the heater element in your O2 sensor is sucking at life a wee bit, although I'm unsure if the ECU even looks at that during warm-up enrichment.

[glion]

its running BP98,

[Navin]

 boon said:

Worth asking, what sort of fuel are you running it on?

Also it could be the heater element in your O2 sensor is sucking at life a wee bit, although I'm unsure if the ECU even looks at that during warm-up enrichment.

This came straight to my mind too, have had this issue before a number of times caused by the oxygen sensor failing. not in a subaru but surely they do the same thing

[Andy_Mac]

Based on what ross was saying a few weeks back they don't use the o2 until up to a set temp so definately wouldn't be part of an issue only occuring during the first 30 seconds of use.