SimonScoobs

Hi All,

My 2009 STI exhaust valve timing is jumping all over the place on both sides! Inlet are stable and within 1 degree, Exhaust are up down up down on constant throttle (with no load) and not together at all bit like a yoyo/see saw and changing values rapidly. Like 9,12,16,22,27.13,8,14 all while holding a steadyish 1800rpm in Neutral. The Inlet sit around 15/16 and nice and stable.

This was discovered on a rolling road and as a side note what software will read Subaru live data for exhaust valve ACDS/VVT as if I strip it all down it would be nice if I could see if they have improved without a trip back to the rollers every time I try something?

It seems odd that both exhaust control solenoids would go together? I am not sure how long this has been an issue as not long bought the car but the previous owner thought something was not quite right as despite large boost and correct fuel ratio, decent torque it is down on ultimate power and has some noticeable hesitations on light throttle around 2-3.5k on occasion. No fault codes will throw as the timing codes together with others have been turned off from throwing a cell light by previous mapper (IE safe to say an out of range code will throw to ecu but this will not trigger the eml light)

Any Ideas would be great to hear.
Thanks for reading.

Simon

bludgod

iTrader: (3)

check the exhaust cam pulleys for damage, if anyone fitted a belt perhaps without using the correct tool the cam pullys will break internally and need replacing. Even if the codes weren't turned off you may not get a CEL for them.

You can live log with an ECUTek ECUConnect or a cheapy VAGCOM cable and the romraider logger software.

SimonScoobs

Thanks very much for your help! My thought too that it is most likely that exhaust pulley on the left bank exhaust cam (the one with the mechanism in). I have a vag-com lead and have downloaded the software but it looks a bugger to get working with all the separate bits to download and sort!
I have no idea how I could inspect the pulley or how they can easily break internally as I thought they didnt have anything much in them in the way of a fragile nature. I guess I will have to take the cam belt off and remove the pulley to check? I heard that you need a special jig 5thou over sized to put them back together properly. How will I know if it is ok, is there a way of telling??

Thanks again, cant wait to get this sorted.

bludgod

iTrader: (3)

on dual AVCS cars the exhaust cams work the same way regular intake AVCS cams do on the earlier cars so the pully can advance/retard the cam timing when requested to do so by the ECU.

Best i can find for pics at the moment is this NASIOC thread of someone tearing down and rebuilding one of the intake pulleys:
https://forums.nasioc.com/forums/sho....php?t=2441411

For fitting/removal you can buy the big spanner/sprocket tool to secure them properly without damage.


Fire me a PM if you need help getting the romraider stuph working, could probably remote onto your PC and set it up for you if you wanted.

SimonScoobs

Wow blud you are an awesome help. Looked at that post cheers, seems everyone agrees that the Exhaust are too hard to service so may have to buy a new one from Subaru! Is there anyone you could recommend trying for a better price on one? Subaru are just under £270 I think.

Do you think I should take out the Ex solenoids from the bottom to clean and check them first? I think the software maybe working (I share a Vag-com lead with a mate and he is away until Sunday so will have to wait and see) Can I buy this???
https://www.ebay.co.uk/itm/USB-Cable...AAAOSwiLdWBqNg

as at £4 I wonder will it work? I had paid around £200 for my other vag-com lead. Thanks for the offer of PM support I will see when lead is here if I have it sorted.

I will just use the logger part I guess to monitor Exhaust valves (I have found) I may order one of those cheap leads just to see what happens. I think all the money in the original vag-com leads was a licence and as Romraider is free it may not need this part of the connector electronics.

I am hoping that once this is sorted it will release the power from the car that it should be making, as at the moment it is, I believe, causing a lack of exhaust gas flow at especially at higher revs leading to overheat in the bores which in turn is causing some detonation and ECU is retarding the ignition timing. I should be getting 50bhp+ given the airflow grams indication on Dyno and all other indications look fine, such as Fuel/air ratio, boost etc. The Inlet timing advance is definitely retarded as the revs rise which may be due, Im hoping, to the exhaust value timing being all over the place as mentioned?

Thoughts Blud.

bludgod

iTrader: (3)

from what I remember - the left hand and right hand are different prices so check part numbers to confirm. ICP would likely be cheaper but I'm not sure if they have any in stock so you might end up waiting a little while either way.

Yes definitely worth checking/cleaning the solenoids first - if there's previously been work done on the car then they could well be gummed up.

The 4 quid cable will maybe do the job - if you have amazon prime you'll likely get one next day for a similar price too but the thing to check for is the FT232RL chipset - some vendors sell them with the CH340G chipset and it doesn't work as well here.

It could well be causing overheat, but also remember if the valves aren't open/closed at the right times then it's just a plain old misfire/knock the same as you would get if you had too much/not enough timing advance. It's just instead of changing the ignition timing your moving when the valves are in the perfect spot for the spark to fire.

SimonScoobs

Well I have tried a couple of other leads I had for now.
1 Auto Enginuity but no connection
2. A generic usb to obd II connector but no connection either.

Does it have to be a Vag-com lead?
Thanks again for your help.

bludgod

iTrader: (3)

no doesn't have to be a vag lead, anything that uses an FTDI chipset and that's presented as a COM port when connected to the machine will work.

MOTORS S GT

iTrader: (2)

Have you cleaned up the earth straps that come from the solenoids to the chassis rail, they corrode badly, & give erratic symptoms like your getting, also cleaning out the solenoids is a good move, as they are at the bottom of the heads get all sorts of gunge build up in them, remove the complete unit from the head & wash out.


As for stripping out the gears, you get very little trouble from them, unless they have been off for a rebuild, & unless removed with the correct tool it causes issues with them, the exhaust gears are more prone to it than the inlets, changing a cam belt should not cause issues, as they don't need any intervention internally.

merlin24

iTrader: (1)

The exhaust AVCS solenoid mounting blocks also have screen filters in them which can get clogged up so worthwhile cleaning them through.

SimonScoobs

Great info guys, The engine has been rebuilt (bill for over 14k!!, ouch) and maybe the pulley has been had it from day one as the chap said he was not happy with the running and took to another mapper and still wasn't entirely happy. I wonder it that left AVCS pulley has been right from the start tbh.

To confirm, Is all the AVCS timing done on the left bank Pulley as I think the RHS are just straight pulleys with no mechanical influence on the AVCS? Correct? Im sure that is what Subaru parts man told me. Also it again seems unlikely that both pulleys would be faulty!

I will clean the solenoids out today But can't see an earth straps mentioned, This is looking on the Subaru exploded picture of the part/heads but I will have a look for them when I crawl under the car just in case!

If my oil was low as some have suggested would this not also effect my inlet vales?

Thanks again.

MOTORS S GT

iTrader: (2)

No, both l/h & r/h run there own triggers / solenoids, some exhaust triggers are the same both sides, so you could swop them l/h to r/h, but some years the trigger has a different bolt location, I think its the JDM 2.0 but I have seen a 2.5 like it, same goes with the solenoids, swop over l/h to r/h, but not at the same time as the trigger swop.

SimonScoobs

Well I doubt if its the pulleys then as I thought it was only one that had the sensor mech in it and find it hard to see both pulleys being faulty. Subaru said that it was only the one on the left!
I have taken one solenoid out (right) but could not reach left as behind exhaust manifold and top bolts didnt move on heat shield! Also they have no filters in them Merlin. Cleaned earth strap.

Both click well and the one i stripped and cleaned seemed to be working fine. I did attach some wires to other one that I could not strip and it clicked and sounded ok and similar to the stripped one that I could see working well.

​​​​​​​It does seem to stutter under light throttle around 2k-3500 and feels at little hesitant at times until you add more throttle. I will data log the AVCS Sunday and see if any different but it felt the same to me!

Do you think this hesitancy and lower power than expected given boost/fuel/air combo can be attributed to Exhaust AVCS running riot?

Thanks GT for the help.

MOTORS S GT

iTrader: (2)

The filters on the exhaust side are in the main body, in one of the oil galleries, if still fitted.


You might be experiencing the fuel stumble at that rpm that some of the 2.5 Hatches suffer from.

SimonScoobs

So no way of getting to them GT without stripping engine? do the filters in the top banjos effect exhaust AVCS?

It is quite some stumble to be fair, lots of flat spot feeling.

It is currently running 413lbs/ft and only 353bhp (should be over 400). When looking at the timing its quite retarded throughout especially higher revs and dyno tuner did have to abort the run due to big detonation which took out 7 degrees of timing. Then he noticed the AVCS all over the place on the Exhaust. So I hope this is the issue, as a note a Leak down test was done previously and passed ok though one side better than the other he said it was ok and not the reason.

I am a long way from any Subaru tuner and want to try and fix myself if possible.

MOTORS S GT

iTrader: (2)

The banjo filters are on the inlet only, the exhaust filters you have to unbolt the avc's main body off the head via the 4 bolts holding it on, as you look into the gasket face of the main body you will see the filter a few mm into the main oil feed drilling, make sure you get the gasket in the right position when refitting, its easy to get it wrong & blank off a oil port.

SimonScoobs

Ah I didnt see the filter looking at the block where the oil was dripping from. I cleaned solenoid and its mounting block, removed the solenoid from that block it sits in and cleaned and airlines, filled with fresh oil and did back up but did not see a filter. Is it up one of the 2 larger holes? And if so how do you clean it as it was not clear to see it when looking up at head holes, though there was lots of oil dripping out.

Thanks again GT mate.

MOTORS S GT

iTrader: (2)

They are difficult to remove without damaging them, but you say its been rebuilt, it might not have any if they have been removed.

SimonScoobs

Trying to read live data BUT I can't seem to get my Romraider Logger to connect to my car. I am using an official Vag-Com Ross-Tech lead Hex+Can and have tried my Autoenginuity lead also. Just says cant comunicate with ECU.
Yet device manager says HEX+ CAN lead working properly

Do I have to pair my lead to the Romraider? I have used my ELM 327 to read live data to my phone app Torque with no issue so it must be the software/lead not working together imo. Is is a case of just plugging in obd and turning on ignition or are there any setting I need to press? unable to connect to ecu init comes up at bottom of Romraider software.
No port is coming up at the top of the Romraider screen and laptop wont let me enter a figure in that port drop down box.

Thanks in advance

SimonScoobs

Spent all day trying to get this Romraider and ECUFlash to connect to the car, followed all the steps that are listed on their site and still no connection. The laptop will not let me override the Ross-tech software as keeps saying its the best driver etc.. I can see the cable listed as a Ross Tech cable on the Romraider Logger software and ECU flash but will not talk to ECU even when correct car is selected from ECU flash manually.

So frustrating!!!

bludgod

iTrader: (3)

with the official cable, when you plug it in does it appear in device manager as a COM port?

With the official cable I think it may only show as a ROSSTECH something cable and now as a COM port (say COM3/COM4/COM5 etc.). if it does show as a com port then double check that Romraider Logger is set to use that com port.

SimonScoobs

Cheers bludgod I think you may be on to something! It does not show as a COM port, just USB device Ross-Tech but nothing on COM section. Neither does my Autoenginuity lead. When I plug in an old serial USB-OBD lead it shows as a COM port device (but this lead wont work to the Scooby as for older cars I think)

Is there a way to force the lead to work as a COM port device?

A localish company have kindly said that if I leave a deposit I can borrow their lead (Tactrix) so I do have a back up option to try.

bludgod

iTrader: (3)

yeh so if it won't show as a com port and it's not a tactrix cable then it's not gonna play ball for you. How much is the deposit on the tactrix - might be cheaper to just buy the cheapo vag lead off ebay/amazon and use that yourself?

SimonScoobs

Thanks bludgod, no idea on deposit, do you mean like this one or any better options you know of?

https://www.ebay.co.uk/itm/USB-ODB2-...53.m1438.l2649

Thanks again

Simon

bludgod

iTrader: (3)

yes that one has the FT232RL chipset as mentioned in my earlier posts so that should work fine. Think i've seen 'em cheaper on amazon though so worth shopping about a bit.

SimonScoobs

On order I will keep you posted.

Thanks

SimonScoobs

Well I connected the lead fine having bought the non genuine one as recommended and the AVCS on intake and exhaust were spot on so maybe by cleaning the solenoids it worked! Anyway they are now both balanced and stable so no stripping cam belt and pulleys for me! Wooohooo!

Thanks for all your help and now for a remap and rolling road setup.

The big question is who do I trust to remap a modified STi and as near to Ipswich as possible???

Any ideas?

imprezagaz

iTrader: (2)

Scoobyclinic have just mapped my modified blob sti and with good results. Worth the run down there

SimonScoobs

Thanks for that but at 180 miles from me its a little too far in case there is any issue. There has to be a good mapper nearer than that.....I hope. London is 80 miles nearer.

trevsjwood

iTrader: (2)

you will struggle for known mappers up the east side. Slowboy Racing near Brandshatch is closer. Alternatively Duncan Graham, google RaceDynamix, he maps regularly at RCM Hinkley and at Surrey Rolling Road, Chertsey, details on his website. Bob Rawle is based in Swindon but does map away from base so may be worth an ask.
Zen Performance, Earith , P28 3PF. They were at Wellingborough but think they moved to Earith, really not sure about them as haven't heard any feedback in quite a while.
Trev