Hit and miss performance MY03 STi
#1
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Hit and miss performance MY03 STi
Wow, posting up loads of queries here....
I think the best way to establish problems or not is through people who own the cars.
I normally do about 10 - 15 mins of driving, pending outside temp, before I will boot it.
I find that the first couple of boots of the day are a little weak, then as I progress through my journey and give it a few more blasts it seems to improve more and more.
Is this quite normal? Does the ECU limit you to a specific amount of boost or something?
Any help would be appreciated.
I think the best way to establish problems or not is through people who own the cars.
I normally do about 10 - 15 mins of driving, pending outside temp, before I will boot it.
I find that the first couple of boots of the day are a little weak, then as I progress through my journey and give it a few more blasts it seems to improve more and more.
Is this quite normal? Does the ECU limit you to a specific amount of boost or something?
Any help would be appreciated.
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I'm not an expert on this stuff but, I did ask similar questions after I got my 1st Scoob.
AFAIK the ECU will hold back MAX boost until things are a little bit warmer..... normally no longer than a couple of miles. I wait a good 10 minutes before giving it any stick, though I'm sure I could do it at lot earlier.
From my experience.... the hotter the Turbo, the better is goes!
J.
AFAIK the ECU will hold back MAX boost until things are a little bit warmer..... normally no longer than a couple of miles. I wait a good 10 minutes before giving it any stick, though I'm sure I could do it at lot earlier.
From my experience.... the hotter the Turbo, the better is goes!
J.
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Just to add to the temperature thing, when the water temp is indicating normal, my Defi's show the oil is barely 55 degrees (normal 95+ degrees) so the engine is way off normal at that point.
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My '05 JDM STI is the same. When it's really cold, it barely limps out of the garage. The ECU definitely holds back performance until the engine is thoroughly warm, and that can take much longer than it takes for just the coolant to reach normal operating temperature. When it IS warm it absolutely flies.
I'm sure my MY00 UK car didn't have this feature - it was much more responsive cold. That said, its engine failed at 61k miles, so maybe the two are related and I'm just impatient?
I'm sure my MY00 UK car didn't have this feature - it was much more responsive cold. That said, its engine failed at 61k miles, so maybe the two are related and I'm just impatient?
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There is also the fact of the ecu memory coming into effect too, by this i am trying to say that the more you boot it, the more the ecu remembers this and alters its parameters to suit for the short term, so your drive will get better as it sets the ecu accordingly.
Again, if you drive sensibly for a lot, then the ecu values get trimmed back to suit that style of driving. On saying all that, i believe it normally does this over say 15 to 20 miles though from what i know.
I know with my modded MY03 WRX, that my car definitely gets better the longer i am driving and is pure poo cold! LOL.
Again, if you drive sensibly for a lot, then the ecu values get trimmed back to suit that style of driving. On saying all that, i believe it normally does this over say 15 to 20 miles though from what i know.
I know with my modded MY03 WRX, that my car definitely gets better the longer i am driving and is pure poo cold! LOL.
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#8
01 cars on I think have a real time updating ECU that works with the current / very recent parameters to allow or not the performance, unlike the classic scoobs that took many miles to re-learn the engine operation and driver style/demands.
The ECU only really pulls the timing back into a safe area, it doesn't seem to optimise to suit driving style, AFAIK ( I am a classic scoob owner so could be talking sphericals! here ).
The ECU only really pulls the timing back into a safe area, it doesn't seem to optimise to suit driving style, AFAIK ( I am a classic scoob owner so could be talking sphericals! here ).
#9
I've noticed this too, and from other threads I've read - particularly one where Harvey was advocating the benefits of wrapping the hot side of the turbo - I'm almost certain that it is purely down to the temperature of the turbo, and has nothing to do with the engine temp or the ecu learning or pulling back the boost.
Some of the newer ECUs do hold the boost down when the oil is cold, but that is only when the oil is properly cold. What I have noticed, and a lot of people on here seem to have noticed the same, is that even after 20 minutes or more of town driving, when the oil is fully warm, the first couple of blasts of boost aren't as quick as the ones that follow.
What I gathered from the discussion on wrapping the turbo was that it performs noticably better once it is hot, which will only happen once you have used some boost a few times, so it's an entirely normal mechanical effect, and if you want to reduce it you could look into turbo blankets or wrapping the hot side of the turbo.
Some of the newer ECUs do hold the boost down when the oil is cold, but that is only when the oil is properly cold. What I have noticed, and a lot of people on here seem to have noticed the same, is that even after 20 minutes or more of town driving, when the oil is fully warm, the first couple of blasts of boost aren't as quick as the ones that follow.
What I gathered from the discussion on wrapping the turbo was that it performs noticably better once it is hot, which will only happen once you have used some boost a few times, so it's an entirely normal mechanical effect, and if you want to reduce it you could look into turbo blankets or wrapping the hot side of the turbo.
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All very interesting comments here.
I drove to work this morning, 40 mins in 30mph traffic and queues, near the end of my trip, nice open road to let rip, so I did. First couple of blasts the boost was pretty good, but not the usual.
Once I went through a few corners in 4th gear, the boost was starting to lift the car nicely. By the end of the corners it was at full potential again.
I drove to work this morning, 40 mins in 30mph traffic and queues, near the end of my trip, nice open road to let rip, so I did. First couple of blasts the boost was pretty good, but not the usual.
Once I went through a few corners in 4th gear, the boost was starting to lift the car nicely. By the end of the corners it was at full potential again.
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Originally Posted by Mr Pants!
All very interesting comments here.
I drove to work this morning, 40 mins in 30mph traffic and queues, near the end of my trip, nice open road to let rip, so I did. First couple of blasts the boost was pretty good, but not the usual.
Once I went through a few corners in 4th gear, the boost was starting to lift the car nicely. By the end of the corners it was at full potential again.
I drove to work this morning, 40 mins in 30mph traffic and queues, near the end of my trip, nice open road to let rip, so I did. First couple of blasts the boost was pretty good, but not the usual.
Once I went through a few corners in 4th gear, the boost was starting to lift the car nicely. By the end of the corners it was at full potential again.
The cooler the air the better
Cheers
Stephen
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This is one of the main reasons I went the whole hog and got a set of defi's. I really wanted to ensure I didn't try to boot it with the oil running cold. It's amazing how long it can take from the water getting to temp, before the oil gets to that 95+ before I let loose. Very simular for shutting down, I'll let the oil drop from 105+ back to 95 before switching off. Invest in an oil temp gauge, it's saved me alot of heart ache :-
Dave
Dave
Last edited by Foxmod; 10 February 2005 at 10:01 PM.
#13
Originally Posted by sti-04!!
Its heat soak mate, you are sitting with the engine not getting much dense/cold air into the inlet, once your out on an open stretch the air is entering the engine & thus giving better combustion
The cooler the air the better
Cheers
Stephen
The cooler the air the better
Cheers
Stephen
From a post on 22b (here - about the 3rd post and after):
"I fitted the DEI kit earlier in the week with a healthy dose of skepticism about whether I'd feel any difference, but suprisingly, even despite the very warm weather, my butt dyno detects smoother and quicker spool between 2-3000rpm. In addition if I've been cruising for a few minutes, whereas it would take a few WOT bursts to feel really lively again before the blanket, it's instant go now. Held boost is higher in lower gears too, and less heat soak to the nearside portion of my TMIC."
Last edited by AvalancheS8; 11 February 2005 at 09:20 AM.
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Originally Posted by Mr Pants!
Foxmod, what on earth does all those controls and dials do?
Is that an official mod?
How much and where can I get that?
Is that an official mod?
How much and where can I get that?
check em out top bunch of blokes
Dave
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