Not starting - No fuel
 

So my 2000 Forester Turbo used to run a bit rough and surge a bit.
I got new plugs, new leads, changed the fuel filter, cleaned the air filter, cleaned the boost controller, cleaned the idle controller and throttle body, then finally I replaced the fuel pump, brand new Walbro. All of that never really made a massive difference.

Its cut out on me a few times and hasn't been wanting to start immediately after. A couple of times after its cut out, I've noticed the throttle cable was loose, so tightened that up. Always seemed to take about 10 minutes to start again, which is why I eventually changed the fuel pump.

The car has been sitting a few months, as It was unreliable even in short distance due to the cutting out. I charged the battery yesterday, it still had enough to turn it over, but as there doesn't seem to be any fuel getting to it, it wasnt starting.

The pump isn't even priming now. I've checked pretty much every fuse, and relay, under the dash and bonnet, with a multimeter. There just isn't power going to the pump now. I have the standard Sigm alarm. I know the pin code as well. Used that and the fobs to make sure the fuel stage off the immobiliser is switching. The red light on the dash does show it should be working. I'm just not sure what else to check now.

A few times after it has cut out, I've done an ECU code scan, using my PSI3 data monitor, but there has never been an engine check light anyway, and it has show historical codes of 22 knock sensor, 45 MAP sensor (also taken off and cleaned) and 44 Boost control solenoid (cleaned with carb cleaner whilst the green connectors have been connected).

The knock sensor is only a few years old, and prior to me replacing, it never used to stop me from starting anyway.

One thing I used to notice shortly before it was about to die, or even when it was surging, is the Ignigiton advance (IG one the PSI3 data monitor) would drasticallt drop, from say 22, to 11 ish then stop.

I've also changed the coil pack a couple of times, but for some known working spares I had, rather than new.

What else can I check?

Check your getting power to the fuel pump when it occurs. Check the plugs on the pump hanger and the one under the rear seat they give regular problems.

Yes I have checked that. From under the seat. Where is the other end of that in the engine bay?

No actually on the top of the tank the large plug that attaches to the hanger.

Ok thanks. Thats the one I have checked. So is there one before that under the seat? I can't say I've ever noticed that one. Is it under the carpet?

I tested the cam sensor today with a multimeter, that was coming up OK, as was the wiring.
I had the main fuel plug pump off anyway, from when I was testing that the other day and plugged that back in. Now when I tried to start it, its like for half a second it feels like a bit of fuel is getting through, all though I can't hear the pump priming.
The next big check will have to be the sigma alarm itself. I've heard about dry solder joints in there.

I've tested the fuel pump connector under the seat, to the fuel pump hanger. Its giving a good reading on a multimeter, so no breaks there.

I'm only getting about 6.3v to the fuel pump, when the igntion is on. Thats not right is it. Is this sounding like an immobiliser/sigma issue?

Have you checked the crankshaft sensor, fuel relay? Also a bad earth can give you issues

Not checked the crank sensor, only the cam sensor. Relays, yes, and various earths.

I'll check the crank sensor, thanks.

As I understand it a signal from the ECU activates the fuel pump relay that is up under the dashboard, that signal from the ecu also goes via the Sigma. If you can find the fuel pump relay try bridging the switched pins on the relay connector to permanently enable the fuel pump, there's a possibility of a damaged relay in the sigma control box or carbon build up on the fuel pump relay contacts.

Checked the crank sensor, all readings good.

The fuel pump relay was reading all good when tested off the car. It did also seems like it was activating during igntion.

I wanted to check the sigma last, as didn't really want to get the dash apart again. I was very close to it the other day getting to the relays, but didn't take it out then. Thanks Shane, I will give that a go.

If the fuel pump relay is switching that rules out the Sigma as I think it only controls the signal to the fuel pump relay and not the feed to the fuel pump. If the forester is like the classic Impreza then the Heater fan and fuel pump use the same type of relay so you could try swapping them. If with the ignition on and you check the fuel pump relay connector you should have a good permanent 12V to the relay, another 12V that switches with the sigma and a good earth, if you're still only getting 6V at the fuel pump then there could be a wiring problem between the relay and the pump.

Thanks for the additional info.

I have taken the Sigma out. Looks like one relay is dead. Another has left a darkish spot on the underside of the PCB, indicating it may have burnt out, but seems to at least have continuity. I do have a spare M30, that I know the PIN for. So I will try switching that for now, rather than make repairs to this PCB. But if you do happen to have the schematics for the Sigma M30, it would be much appreciated.

The sigma is spliced into the main fuel pump wiring you'll usually find it spliced in along the edge of door you'll spot it a mile of due to the thin gauge alarm wiring spliced into thick gauge fuel pump wiring and that's the reason it burns out the sigma fuel pump relay. You can just bypass it and the sigma will still function by cutting the starter. The third relay controls the indicators flashing. Good tell tale for that failing is that the indicator will start to stick on on the driver side when you lock/unlock

I've used an older M30 alarm I had. Been left outside, so not great condition, I'm going to give it a good clean up. I'll post some pics later.

I'm pleased to say it now started with my old M30. I knew the code on that, so used the keypad. Success. For now

thanks for all the advice.

Did it look like this?

https://cimg0.ibsrv.net/gimg/www.sco...60782a6e9b.jpg

Yes it did. But it still felt like that relay was working. It did have continuity at least.

So in theory, I could replace that relay and it would work?

Worth re-flowing all the joints, this was one of mine.

https://cimg9.ibsrv.net/gimg/www.sco...49900c6f32.jpg

If you can find a replacement set of relays I'd be interested, the range in the Sigma are now obsolete, if I ever get back into the office I'm going to ask our component engineering team to see if they can find a drop in replacement.

Yes I will check the board over properly, just pleased to get it running for now.

Here is the data sheet I found on the actual relay: https://datasheetspdf.com/pdf-file/7...RWH-SS-112DM/1

No longer manufactured it says here: ORWH-SH-112HM3F,000

I'll keep looking, and if you do find them, please let me know.

Some interesting info on the relay, and possible other solution here: https://uk.subaruownersclub.com/foru...ator-stuck-on/

Glad you are getting somewhere.