dynamix

iTrader: (3)

I'd be prepared to bet money it was just map related with the one size fits all prodrive map not actually fitting your car and could be mapped out.

weatherman

How much money, £350 + 300miles x mileage rate
Any idea what gains (if any) there would be on a PPP?

dynamix

iTrader: (3)

YHPM

scoobiewrx555

So why don't you do yourself a favour and drive to the tuner saving yourself the mileage costs or better still get a handful of mates in the same area to chip in and not only get a discount on the cost of your remap but you all get to share the tuners mileage costs as well. That's how a lot of mobile tuners operate if they have to go a very long way.

300miles@40ppm = £120. That usually includes not just the cost of fuel to and from but also the time it takes to get to and from a client. 40ppm is about par for the course with a lot of mobile service based trades. 150miles each way will take a couple of hours or so each way to travel so that makes for half a day or more total travel time.

carl heath

hope you keep us posted as to weather this is sorted via a bespoke map mate?

weatherman

Will do. The only poster on this thread who had a custom map and had a problem only seemed to complain about the mid range jerkiness, not the low boost syndrome, so hopefully a custom remap will fix it. (No-one on this thread has tried this yet?)

It will seem to be fixed at first as it is always OK after a restart, it will only be after some long journeys that I will be sure....

Smiler AS

Feel for you bud, its frustrating.
Ive just been out and installed NGK Grade 7 plugs (Mitsibushi EVO plugs gapped at 0.6mm as opposed to std. 0.7mm) and running fine (the plug under the air pump is a bu**er to do), but I know its only a short fix as Im pretty sure im overfuelling and seriously reducing the lifespan of the plugs. Im due for a custom remap next couple of weeks. Fitting 3 port boost solenoid too and installing an in line fuel filter. Removing the in tank fuel filter (introduced on the 2.5's) as the seal ring was previously leaking when under demand and its not in a place I can keep an eye on. (poor design subaru).
Il keep you updated.

PS. Similar to you, if I disconnect battery overnight, it runs perfect for 1st ten mins then the hesitation comes back, think due to the overfuelling causing det knock and ECU gets in a mess. As above a custom remap is surely the way.

Also, when I do pull through the hesitation, sometimes I would only get 1.3bar boost but recently has been back up to 1.5bar boost.

Was reading today about spark blow out, just another idea thrown in, but would it possibly relate to me changing plugs as above.

Im hearing some dodgy stories about Tesco 99 (which I have been running a lot recently) but last tank was V-Power, will keep using V-Power for a few tanks to see if any results.

Am going its something to do with timing, ignition, spark, fuel - all of which can be dealt with with a custom map??

weatherman

Smiler, Boboskins, Iuchabar et al, have any of you happened upon a lasting fix?
My symptoms have recently become semi-permanent but this has given me an opportunity to analyse them a little bit more.

I'd noticed that during slow mode partial accelerator pressure changes the car from steady speed to modest acceleration, but that any further throttle pushing was having no effect. I'd also noticed that a tell tale sign of slow mode was the surging at partial throttle around 2700rpm.

Today I decided to test this. In 5th, at 60mph, the car should reach 80 in just over 5 seconds, in slow mode though, 11.5 seconds. I sat at 60, then depressed the accelerator just enough to start gentle acceleration. This isn't much of a change in throttle position, though the acceleration is almost instant, a step change which seems more urgent than a standard car, but only seeming so due to the relatively big response to small input. Anyhow, keeping the throttle steady, that is just slightly depressed from the steady speed setting, resulted in reaching 80 in 11.5 seconds.

I slowed back down to 60, then planted it to the floor, and it still took 11.5 seconds to reach 80!

There seemed to be only 2 acceleration rates, modest and nothing at all, with nothing in between, like an old computer game using keyboards.

There is a third acceleration rate, negative, if I take my foot off the pedal entirely.

Now, this also explains the link between slow mode and the surgy jolty feeling at partial throttle at 2700rpm. IF you get the throttle position just right (or wrong?) the car is flipping quickly back and forward between steady speed and its one and only (modest) acceleration rate. As there is nothing in between you get the surging, which can be quite violent. It is not fuel cut due to overboost as I can always pull through by accelerating harder.

Now, at higher revs acceleration does tend to improve, not to what it should be, but still better than at lower revs. This indicates to me that it is not some physical limiting that restricts low-medium rev performance, such as fuel pump or leak, as I would not get any better performance at higher revs if the fuel pump was already at capacity at low revs.

Also, until very recently, slow mode could be cured by turning the engine off briefly and restarting, again eliminating a physical cause.

So, I am coming down ever more strongly towards either a throttle position sensor problem, or more likely, a mapping issue. A faulty Throttle Position Sensor should throw an error code but diagnostics show nothing. I wonder if it is possible for a dodgy mapping to fall back to a simplified mode (deceleration, steady speed, and acceleration but since I, the ECU, have either lost my memory or full sensor information, I am only going to give you a very small safe and fixed amount of acceleration). Doesn't seem as slow as "limp mode" though.

Anyway, I think I am going to ask for funds instead of pressies this Christmas and go with a remap.

scoobiewrx555

I've not gone back to read the whole thread through even though i've contributed before so if you've already done what i'm suggesting here apologies for the post.

Have you tried getting getting a tuner to flash a new fresh standard Prodrive ROM to the car. At least that way you can eliminate anything to do with the ECU/mapping. Once in a blue moon the ECU/mapping gets it's knickers in a twist and the ROM/Software becomes corrupted and can/will make your car run rough/oddly. After all your ECU is a computer and can be subject to the same issues as other computers.

If it's still running the same after that then it's more likely an electrical/sensor issue. Then you'd have to get a bit more involved and properly log what's going with a laptop either while on a rolling road or on the road but that will cost you whoever you go to.

If you're not too far away from me and you're happy to travel to Northants i'd be happy to flash a fresh uncorrupted Prodrive image to your ECU free of charge. It only take s a few minutes. At least that way you can quickly find out what the score is.

Sometimes i come across a scooby that for no apparent reason can run a bit rough or just not right when there are no sensor/electrical issues at all. A reset doesn't always work and i find a freshly flashed ROM can do the job. It's just one of those things.

Hope this helps.

Francis

weatherman

Thanks for the offer, though I am in Scotland! Don't suppose anyone up here can provide such? I just assumed that it would cost as much for a Prodrive reflash as a remap, though if it takes so little time then maybe any Subaru dealer could do it?

scoobiewrx555

Just reflashing the same map on is money for old rope. It really does take a few mins to do but they charge silly money to do it. However, once you get a car on rollers or on the road to do any fault-finding that costs money as it takes time to do.

Actually i'm in Pitlochry for the week as from next weekend if that's any good to you.

If i can help give me a shout.

EngineMapper @ Group B Motorsport

The Hawkeye models and a lot of the bugeyes exhibited a similar sort of stumble off boost that was solved through a number of methods not just changing the map itself.

The Hawkeye WRX without the PPP has a terrible flat spot on 10-20% throttle off boost and the PPP just exaggerates this problem with it's aggressive style drive-by-wire strategy, the STI is even worse! The emissions strategies implemented on these cars are to the detriment of the drive ability.

What's worth doing is getting someone to drive your cars that is used to dealing with these on a day to day basis to see if it is something that is unusual to that specific car. That will then give you the right information to then either solve the problem that has arisen, or solve the stumbling on the map that has always been there.

Hope this helps,

Graham

boboskins

Weatherman,

Not sure it helps but I can tell you how I went about things.

I was lucky enough to have have a local Scooby enthusiast nearby (Cheers Wuz) who was able to take a look at the ECU and he noted that the ECU was acting as if there was knock present - from memory the advance multiplier which would normally be quite high (16 - again from memory) was sat below 1. As the typical causes of knock were eliminated and knock was ruled out I was initially at a loss to what to do next.

In the end I decided to kill two birds with one stone and embarked on some modifications - VF43 turbo, exhaust change, fuel pump etc and got a remap from the somewhat legendary Andy Forrest. End result was a stunning change in performance. Interestingly though, during the remap Andy spotted a brief moment when there was an indication of knock on the ECU (although as he was monitoring for knock and knew there wasn't any). It looks like, in my case anyway, there is something a bit off with the knock sensor. It may be overly sensitive and picking up something else from the engine. Performance is still stunning - but I do still get periods when performance drops for a while.

Knock sensor doesn't appear faulty - but I think I am going to look at re-seating/swapping out the knock sensor. Would be good to finally get rid of the issue, but the mod's & remap (that wouldn't have crossed my mind if I hadn't had the problem) have been well worth it.

B

weatherman

Actually passing through Perth next Sunday afternoon I could make a wee detour if that suits?
Passing through again on the Wednesday and Friday evenings if any better....
Stuart

scoobiewrx555

Wednesday is probably better but earlier in the afternoon if that's not a problem.

Perhaps we can meet at a lay-by or somewhere halfway between Perth and Pitlochry on the A9. Won't take a few mins to flash a new ROM on your ECU and take it up the road and back to make sure it's playing ball.

PM me and i'll pass you my number. a chat on the phone would be useful.

Francis

dynamix

iTrader: (3)

tbh it isnt unusual for the hawkeye ecu to register false knock and have regularly seen the ecu take out 10+ degrees of timing in cruise areas on unmapped cars for no apparent reason. Very difficult to say exactly why they do it but there can be many reasons such as slight rattles on the heat shields or even injector opening/closing at a certain frequency can be enough for it to think there is some nastiness going on when in fact all is good.

weatherman

Duncan Dynamix took a look at the car while in its recent permanent slow mode and when hooked up to the laptop, found that the advance multiplier was sitting at 0.38. A quick ECU reset restored unity and performance. So after carefully listening to the engine under load it looks like a heat shield has been causing false det.

Interesting that up until recently the ECU was resetting itself after an ignition cycle (maybe not a full reset) but then started remembering about the false detting problem until a proper reset...

Any thanks to Duncan and the community for the help!

Stuart

jimbojones1000

Ive got a very similar problem with an MY08 STI, i'll be having a good listen for any rattly parts after reading this thread. I have the same odd situation where its sometimes slow and sometimes not. Loggin the problem showed a clear difference in boost(couldnt look at det PID on current cable, so ordered tactrix to use ecuflash logger) 9psi in slow mode 16-17 in normal mode. Thanks for the thread its helpful to know your not alone!

weatherman

I think the originator of the thread has maybe given up as they haven't posted for some time!

Duncan suggested getting an ODB cable to reset the ECU should the problem recur. I take it that means bying a Tactrix ODBII cable and connecting to a laptop/notepad with ECUExplorer as described in Scoobypedia http://www.scoobypedia.co.uk/index.p...ledge/ECUReset and also installing ECU Flash to allow the cable to work, as described at
http://www.scoobypedia.co.uk/index.p...ctingToYourECU

That article refers to additional connections if reading/reflashing ECUs, but not if datalogging. I wonder if the connections need to be made for a reset?
Stuart

jimbojones1000

I dont think it does, it should be a standard command which even some elm327 controllers can mange, the re wiring i believe is for older ecu's and some cars which require a current on a pin to write the map, 04 on subarus dont require this(that last statement is based on vague recollections etc but i think its broadly correct) I ordered a tactrix because i knew it would definitely work with learning view, from rom raiders site, so i can see the learning tables and perform the reset. Also i should be able to reflash the orginal rom back on.

Most infuriating thing about it is you dont know what car your gonna be driving, one minute its fast and what you expected the next its not, i had convinced myself it was just me until i logged the boost levels. Cable comes tomorrow, ill see how it goes.

dynamix

iTrader: (3)

Stuart - just a std vag.com cable from ebay will do the job to read the ecu or a simple obd code reading tool from ebay will do it too - they cost about £20-30 and will reset the ecu should this ever happen again but tbh when the heat shield is fixed it will disappear as an issue IMO.

weatherman

Thanks Duncan

Car still running fine just now!

Stuart

jimbojones1000

I couldnt get the OBD2 cable i had to work thats why i ordered a tactrix.

I checked the IAM with learning view and it seemed fine 1.00, however i dont know if i had previously reset the ecu with a terminal command i tried whilst waiting for this new cable, so i reset it anyway and all was fine, it added a correction to the fine knock table in the top row but then a day later that had gone(dunno how that happens?) and still all was fine, today however the car suddenly went slow again, and i checked the IAM and it had dropped to 0.3125, and the fine knock table had a load of entries, one at -5.6, 0-<2400.

Ive reset it again to see if it will run fine and then have a sudden bout of knock again. It seems to me like perhaps mine is also something like the exhaust shield. Is the shield you refered to the one around the turbo? I had a poke at it today but it didnt seem loose, although i suppose it doesnt have to be actually loose to vibrate at the right frequency for the knock sensor to pick it up. Might just try tightening the bolts i can see and get to easily.

any advice gratefully accepted.

BrownPantsRacing

iTrader: (6)

My 06 Hawkeye WRX experienced this problem last Friday. Was at partial throttle overtaking stationary vehicle, all seemed fine, but couple of hundred yards later when trying to put my foot down it had virtually no power.

My car is running 334bhp with VF48, STI intercooler, sports cat downpipe, walbro pump, Do luck filter, HKS SSQV and a Duncan remap. Been running like a dream for last 3 months since the remap, really can’t fault the car. Never had this issue before when the car was standard and this has only happened the once.

Duncan pointed me towards the ECU problem and thankfully I already had the car booked in at FB Tuning for Rich to fit new heat 7 NGK plugs and change my Poo-luck filter to a K&N type. Rich had a look at the ECU and the multiplier was sat fixed at 0.0. Car was still in slow mode even after switching off a few times on Friday and leaving over night. Thankfully an ECU reset on Saturday sorted it.

There was signs of very very slight det on 1 of the spark plugs when we removed them, but nothing at all to be worried about thankfully.

Car been running perfect again since. Don’t know what caused the problem, as Duncan suggested I think the ECU got its knickers in a twist! Strange cars!

Thanks for all the help and advice again Duncan. Top man!

Andy

weatherman

Yes it is embarrassing when you have trouble overtaking a stationary vehicle

0.0, even worse than my 0.3. Interestingly at a service previously I had oil noted on one of the plugs as a possible reason for the reduced power, though was probably another red herring.

Jimbo, not yet identified which heat shield (if any) is the one responsible for the knock detection though I suppose anything which vibrates at the same frequency as the piston (i.e. connected to the engine speed) must be at risk of annoying the knock sensor.

Bob Rawle

A bit of input to this, Phantom det as its mostly called, is not something that normally pulls the advance multiplier down, it will cause the ecu to take anything up to 20 degrees of ignition knock retard out dynamically but will not affect the AM. So, if your cars had a reduced AM to that level then whatever caused it was not PD and could be something "real".

From my perspective those of us that use the EcuTek software now have the ability to rescale the knock sensor output to resolve a true PD issue without affecting the ecu's ability to react to anything that could cause damage.

So keep an eye on your cars as you might have an issue. As a precaution a leak down and compression test would provide piece of mind and eliminate the piston ring land issue.

cheers

bob

BrownPantsRacing

iTrader: (6)

That would make sense, my spark plug showed I had the smallest amount of det when removed.

jimbojones1000

I had started to wonder if it might be more serious, i was logging the fine knock correction and IAM when it dropped from 1-0.3 once and it seemed like the fine knock went mad and then the IAM dropped, but i guess without other information its hard to know what was going on. I was only logging IAM FKC RPM and MAP.

Ive been putting off doing the dreaded comp test, ive not done anything on a scooby before, and i wondered if there is room between the body and the plug hole to fit a standard comp tester, with the long brass end? Its hard to tell as i dont know how long the coil pack is. Dont want to get it off and find i cant get the tester in. I'll get a garage to do it if you need something special.

Probably should have looked into 08 sti hatch engine trauma before buying one!

Thanks for the info

BrownPantsRacing

iTrader: (6)

To be honest, as most people have said before the biggest problem and cause of engine failures on the 2.5L 06 onwards engine is the standard map. A generic one size fits all map will not suit all engines. Likewise for the PPP map.

If I bought a hatch the first thing I would do is spend £350 on a remap. Duncan, Bob, graham, Simon or any mapper will get the car running to avoid all det and knock. I would get it looked at by one of these guys first before spending too much doing compression tests etc.

jimbojones1000

Car seems much better and IAM is back to 1.00 must have dropped as yesterday was at 0.85, the fine knock entries seem to be dropping also, all since putting a tank of Vpower in instead of momentum 99! I never thought a car could be that picky with regards to additive payloads in high octane fuels, but apparently it is!