New Syncro! But not starting

Hi folks

After hunting for a few years I finally found myself a '91 Syncro with a Subaru EJ20 engine. Stoked.
The downside is it is now not starting - it’s turning over, fuel pump is priming but I don’t think the ECU is getting power. I’ve tried replacing cam and crank shaft position sensors.

Suspect that the main culprit is the starter relay - anyone have any idea where I can find a replacement?


Not sure exactly where you are but ebay is often an easy place to get parts.

What sort of starter motor do you have?

Did this van come with the no-start issue or did it develop?

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ECU has power if its priming the fuel pump. What about the Subaru ignition key, I assume its there, perhaps some wiring around it.

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It’s the original VW starter as I understand it but that works ok. It was starting the first week I had it, then died over the weekend. Part of my thinking behind it being the starter relay is that it is veeeery corroded (Perth sea breeze etc).
I think I’ve found the right relay via a Subaru facebook group so will plug that in and see how it goes

Excuse the ignorance…does the fuel pump not have a separate relay? The reason I think the ECU is not getting power is I’m not getting any engine check lights coming on on it - even when I connect the diagnostics wires

Depends on the conversion I guess, the Subaru ECU normally controls the fuel pump relay which is why I assumed that ECU has power and if ECU security hasn’t been bypassed it needs the Subaru ignition key to be working but I know mine (EJ25) does fire but stops almost instantly when the key is out.

Are you using an ODBII reader

Perhaps trace the ignition wire to the ECU where a Voltage check will confirm if its getting power.

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Yes the fuel pump has a separate relay which is a brown square shape from memory. Or maybe a silver round one - cant remember now. Probably different between EJ25 and EJ20 versions anyway.

They aren’t very expensive to replace anyway.

The brown is the one! Was surprisingly tricky to find the exact one - not many 6-pins around any more. The other silver one is the fuel pump on mine. Picking up this arvo, fingers crossed…

ECU is one of the older ones without OBDII sadly. I am reading some voltage (10V, up from 9V after cleaning the ground) but not the fuel 12.6V that the battery is showing me

Believe there was once a factory subi immobiliser which has been removed along the way

First up make sure your ignition switch has not failed(known problem with the T3), you will lose power to the ignition in the start position. Second are you getting any codes from the check engine light, if you don’t have a light wire one up.

If you fuel pump is priming your ECU has power as it controls the fuel pump. Does not mean that is keeping power.

I do have a light wired up to the ECU but it’s not lighting up at all - not when I turn the key and not when I connect the diagnostics wires either.
Got my heads on a relay and that wasn’t the problem, sadly.

Not sure how your no start issue is going, yet if your ignition switch is good, try the ECU reset - I assume yours runs a factory ECU?

This is a good ECU re-set procedure which may help.

Classic (JECS) ECU Reset

Ensure engine is at normal operating temperature, turn engine off
Locate the two ECU connectors, located under the steering column and consist of a black plastic male and female connector, and a green male female connector
With the ignition OFF connect black to black and green to green.
Turn on ignition, do not start the engine, depress the accelerator pedal to full throttle, then return it to the half-throttle position and hold for a few seconds, and then release
Engine Check lamp turns on
Start engine and then drive for at least one minute, keeping road speed above 11 Km/h.
ECU is now re-set.
At this point the check engine light should start to flash the all clear signal (steady 1/2 second interval flashes). If the check engine light does not flash, or indicates some other sequence, there is a fault present in the system, and should be professionally checked for necessary repairs.
Stop the car and turn off the engine.
Disconnect the black and green connectors.
Job complete

Thanks for following up Scott, unfortunately the engine isn’t getting spark and fuel isn’t getting to the spark plugs so starting it as part of that reset isn’t an option.
Bit of an update - I have a new ECU coming from the UK so crossing my fingers that works.
A couple of the resistors on the old one were fried - I soldered replacements onto the board but no luck. Fingers crossed.

Had a similar problem of no spark with my 1989 VW Syncro only a few weeks back. Note, my vehicle has an original 2.1 VW motor. Problem ended up being a broken wire within the harness from the hall effect sensor to ECU unit, the break occurred in a very unusual position, obviously due to age deterioration. From experience these type of problems always come down to very small issues.

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From memory, my van had 3 main fuses on the ignition side. I accidentally forgot to put a fuse in one and my first start didn’t work until, I realised I had neglected the fuse.

Once replaced it immediately fired up.

As said I bet its something really minor…