Subaru Legacy Emer ECU

[richyb66]

It's been a good while since I've posted on here - 2 years and 50K miles of faultless running (no doubt due to the excellent conversion Tubbs did on the car for me). However this week it started to play up and won't stay running on gas.

I make a point of changing gas filters every 12k miles without fail and there nothing obviously amiss with any of the wiring but it will only run on gas for a maybe a couple of minutes before beeping and switching back to petrol

Having had some experience with the Bigas system on my previous S6 (not without it's issues!!) I decided to splash out on an AEB diagnostic lead from Tinley Tech and have a quick look for any stored fault before I resort to the professionals.

First question is what's the best software to run, I know a lot of the ECU's are just rebadged AEB's so I tried the AEB Leonardo software but I can't get it to connect to the ECU and I don't know if it's an issue with the lead (had problems with the Bigas lead and Sgis software in the past and it was often a bit flaky) or the software version. Despite coming with a driver cd, the usb interface with the lead seemed to install when connected anyway and I wonder if it might an issue with the wrong interface driver.

Second question, the solenoid in the multivalve on the tank is sometimes a bit noisy so I have a look at this first, it does seem to be working and I took the coil off and tested it and it seems OK. I assume that with 3/4 tank of fuel, I can't remove the actual valve - the multivalve has a manual tap on it but it looks like this shuts off the filler, not the outlet?

[Gilbertd]

Although the ECU is AEB it is flashed with different firmware depending on who it was supplied to and can only connect to the correct software to match the firmware. So although they all use the AEB 2568 ECU an Emer one will only connect to Emer software, a Bigas one will only connect to Bigas software, a Zavoli one will only connect to Zavoli software, etc. So you should have bought an Emer lead from TT rather than an AEB one, then it would have come with the correct software. TT should be able to supply you with the correct software if you admit your mistake and ask them nicely. AEB Leonardo was/is a single point system so will be completely different and the software will only ever connect to an AEB Leonardo controller (which is an AEB 175 and not an AEB 2568).

[richyb66]

Thanks for that. I couldn't actually see a specific Emer lead on the TT website and so I got the AEB one ( Ref: E000-USB-LEAD-AEB ) because it said it was Emer, OVML, Bigas etc).

I'll give TT a call today and explain the problem and see what they can do.

[Tinleytech]

Hi,
The lead will be fine for your Emer ECU (or any other AEB) - you just need the Emer software which you can download from the page below :

http://www.tinleytech.co.uk/downloadnd


Regards

Tony.

[richyb66]

Thanks Tony, wasn't expecting to get feedback quite this quick (great service from TT as usual).

I'll download the software tonight and give it go.

[richyb66]

Software downloaded and installed in under 5 minutes.

Hooked up to car and connected to ECU with no problems.

Tank Solenoid Valve fault stored. Cleared fault and ran car on gas until it cut-out aging. Tank Solenoid Valve fault re-appeared. I gues the strange noises might have been a clue.

New solenoid and valve ordered from TT. I'll swap the solenoid and hopefully run the car until the tanks empty, then I'll swap the valve.

Thanks again to Tony.

[57jam89]

My tank solenoid makes a very funny noise then it opens on my Hyundai Coupe but it's still working fine.
Keep this thread in mind in case it plays up.

Thanks.

[Tubbs]

Sounds likely that the solenoid plunger inside the stem post has got gunked up and burnt the coil out.
Turn off the tank (yellow lever), run engine with the tank off until it switches back to petrol, remove the solenoid coil. Undo the stem post. Some gas will come out. Hopefully not lots. But use a long 16mm socket so you can keep your hands out the way. Clean out the plunger. Brake cleaner is good for this. Some wd40 in the stem post with the plunger and work it in and out.
Re assemble with new coil. And hey presto ! Another 50k or perhaps more ?
Always nice to hear from happy customers ! Glad it's behaving itself. Subarus are a very good conversion. Yet another big thumbs up for flashlube combatting valve seat recession eh !
Keep your eye on the fluid level though pal.

[richyb66]

I did think that the solenoid plunger might be sticking. I turned the yellow tap off and undid the stem post but the gas seemed to be coming out for ages so I did it back up. With 3/4 tank of gas I thought it'd take hours to empty but if it's only purging the pipe and the front end, I'll give it another go when the new bits turn up.

Experience with my previous S6 which didn't have the best conversion on it has taught me that every extra penny spent on a quality conversion pays dividends in the future. Apart from this small glitch the Surbaru has run like clockwork, still pulls like a train on gas and and the H6 engine does seem to take to a good installation.

I still keep a note of the gas I'm putting in to help monitor the Flashlube level and top up when necessary. I tweaked thew flow rate very slightly early on and now it using around 1ml/litre gas as it should be.

Nearly 2 years on, still a very satisfied customer, well worth traveling a few more miles to a reputable installer.

[LPGC]

My tank solenoid makes a funny noise....

Dunno if you have an AEB system but certain firmware versions on certain AEB systems can make the tank solenoid make a funny 'rattling' noise when switching over anyway, not seen that on Emer though. The rattling could be prevented by ticking/unticking the 'open solenoid coils in advance' box in AEB software. The rattling 'feature' seemed to come about when sequential changeover was first introduced (instead of switching all injectors at once) on AEB systems-and go away on later firmware. It could be argued it is beneficial, the rattling is due to quick pulsing of the solenoid which might help unstick a sticking solenoid...

If there is any noise from a tank solenoid it might still be working - In which case I'd also look at the reducer solenoid (does that click too?). On AEB systems (particularly 5/6/8 cylinder installs) the blue wire to reducer solenoid and blue/white stripe wire to tank solenoid are often mixed up (sometimes due to minor installer error / sometimes due to an installer correctly reading an incorrect wiring diagram but not knowing any different / there have been some contrary wiring looms)... None of which is an issue, as long as misinformation (in error reporting - due to wiring mixup) doesn't have you replacing the wrong coil.

I did think that the solenoid plunger might be sticking. I turned the yellow tap off and undid the stem post but the gas seemed to be coming out for ages so I did it back up

Gas coming out for ages implies the tank solenoid isn't at fault... because if tank solenoid is at fault we wouldn't expect much gas to come out of lines between tank and reducer (engine is likely able to run on the liquid gas in lines between tank and reducer until it's been nearly all used up)... But it depends on what you mean by 'coming out for ages' - if you're just opening the post enough to hear a very gentle hiss then that might be just residual vapour. Not a great idea to have loads of liquid gas coming out at a fast rate for a long time anyway, can destroy the green/brown rubber solenoid post seal if you further turn the post when seal is extremely cold...

Tank coils are by far the most likely to go wrong though...

Simon

[richyb66]

When I undid the post I expected to get some gas leakage so I kept my hands well clear and undid it until the gas just started to escape in a controlled manner (maybe lifted 0.5mm off its seat). I was mindful that if it undid completely or wouldn't se-seal, I'd have along wait for it to empty. I gave it maybe 5 minutes to de-gas and then gave up and screwed it back in.

When the parts turn up, I'll try again. I'll fit the solenoid, isolate the tank with the yellow tap and then run it until it cut out like Tubbs suggested. Then I'll swap the valve. I'll also try and do it in the daylight, not at 9-30 at night like I did last time!

[LPGC]

Yeah, also I should have added - agreed with Tubbs suggestion, turning the yellow lever off should mean the engine can run on LPG until all the gas in the line between tank and reducer is used (thus preventing much gas coming out when you undo the solenoid post). Still, if a lot of gas comes out of the line when you slacken the post, that might point to reducer solenoid valve instead of tank solenoid valve but could equally point to an issue with the tank solenoid coil that is intermittent (gas in line because tank solenoid has opened to let gas into line but system refuses to run on LPG because LPG ECU self diagnostics notice an electrical issue with tank solenoid coil). Sometimes on older AEB ECUs phantom errors are picked up, when this happens the system will switch back to petrol (usually with longer duration beeps that the usual length beep when you run out of gas) - In this situation, as long as pressure and temp readings seem correct the problem can be sorted most easily by unticking 'enable diagnostics / error reporting' in software.

Simon

[Gilbertd]

Although don't forget that 1 litre if liquid makes 270 litres of vapour. If you've got an 8mm feed pipe that's maybe 3m long, that's almost 3/4 of a litre of liquid so it can take quite a while.

[LPGC]

Although don't forget that 1 litre if liquid makes 270 litres of vapour. If you've got an 8mm feed pipe that's maybe 3m long, that's almost 3/4 of a litre of liquid so it can take quite a while.

Agreed, that's why I said a slight hiss might not be enough over only a few minutes.. Serviced a BRC system today, no manual shut-off valve (yellow lever or the like) on the 4 hole tank, wiring and plug on tank solenoid difficult to access, so when changing the liquid filter I hadn't first purged the tank to front line. Undoing the bell end bolt on the BRC filter solenoid, the line was purged within seconds but I didn't mess about undoing the bell end bolt, had new seals and O rings ready to fit anyway. It is generally easier to control the hiss (escape rate) on tank solenoid posts than at the other end (front end filter solenoids), because the posts are a much smaller diameter... If you're worried about too much of a hiss, much more likely to prolong line emptying time if working at the tank end.

What you don't want is escaping liquid gas hitting you in the eye.. that hurts!

Simon

[richyb66]

Sometimes on older AEB ECUs phantom errors are picked up, when this happens the system will switch back to petrol (usually with longer duration beeps that the usual length beep when you run out of gas) - In this situation, as long as pressure and temp readings seem correct the problem can be sorted most easily by unticking 'enable diagnostics / error reporting' in software.

Simon

Interesting, the beeping I'm getting is longer duration. Would a fault with the reducer solenoid still be logged as a tank solenoid fault?

I managed to swap the valve and solenoid on the tank on Friday and initially it ran OK but it did cut out again. As I only had limited time to have a look at things, I have best use of the daylight the visually check the wiring front end to the tank for damage. Everything looked OK with no obvious damage and the invisible areas were where the wiring is well protected behind under body shields (a big assumption I know).

I cleared the fault and left it running for 10 minutes and it ran fine. As I'm not using the car this weekend I've not have the chance to give it a decent road test, I'll be back in it next week so I'll see how it progresses.

[Gilbertd]

There are often, but not always, two feeds for the solenoids on an ECU so the two can be wired separately. In this case a fault will be flagged on the offending solenoid. If both are wired to the same feed, or there is only one, then a fault on a reducer solenoid may well be flagged as a tank solenoid fault.

[LPGC]

Slower beeping informs of the LPG ECU detecting an LPG system electrical problem - We know you have or have had such error as you've seen tank solenoid error logged by the LPG system. All 5/6/8 cylinder AEB2568 ECU's (such as yours) have a separate feed for tank and reducer solenoid, these must both be wired up else the self diagnostics will interpret a solenoid coil failure (though you could use only one of the feeds to power both solenoids and disable self diagnostic error reporting to prevent error being logged for the unconnected feed. You cannot pick and choose aspects of error reporting to turn on/off, you either turn off all error reporting or connect both solenoid feeds respectively to each solenoid, we know your error reporting is enabled, you didn't mention enabling it, presumably vehicle ran on gas OK before this issue, so we know both your feeds are connected respectively to tank and reducer solenoid. If feed wires are mixed up (tank solenoid feed connected to reducer solenoid feed and vice/versa), system would report tank solenoid coil fault when error is actually reducer solenoid fault or vice/versa - Wouldn't think this to be the case on Emer as reducer coil feed comes with plug already attached to loom which plugs straight into socket on reducer solenoid where-as tank solenoid wires are just bare wires.

Simon

[richyb66]

Well so far, so good. Put 40 miles on the car today and no problems. Included a thrash down the motorway so hopefully it was the tank solenoid.

Thanks for all the advice, regardless of whether the fault reoccurs, at least I've got a better understanding of how the system works and I've got the tools to do more detailed fault finding should the need arise.