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Re: Hello owner

Posted: Mon Feb 22, 2021 7:11 pm
by Stickfinger
Cheers....will try that

Re: Hello owner

Posted: Tue Feb 23, 2021 7:10 am
by Dieselman
As above, I suspect air in the fuel supply, but it would be worth checking why the starter isn't receiving a trigger signal.
The start inhibit relay is mounted behind the left headlamp, then the power passes to the engine loom via the connector under the LHM tank.
The glowplugs are fed directly from the GP relay, but the fuel pump stop solenoid, the pump and Ecu, are fed power via the connector under the LHM tank.
The STOP solenoid is a secondary device, the pump/Ecu will stop fuel being delivered if power is lost.

Check fuel supply to the pump and check for all power and Gnd at the Ecu and pump.
Read the engine codes.

I'm not sure if the Epic system is covers in Gabor's circuit diagram, though it's worth remembering that this was a running car before belt failure.
Don't go too deep, too fast.

Re: Hello owner

Posted: Tue Feb 23, 2021 8:35 am
by Stickfinger
Thanks chaps, lots to check. Will get it on the LEXIA today.

Re: running car before failure.....yes, but it has not run for about 4-5 months since it failed, as such I do need to check some of the basics like corroded relays and failed leak-off pipes as well.

Re: Hello owner

Posted: Tue Feb 23, 2021 1:55 pm
by Stickfinger
I am informed the EPIC pump cars do not have a stop solenoid as it is "part of the pump"

Re: Hello owner

Posted: Tue Feb 23, 2021 4:08 pm
by Stickfinger

I have: Flow return, replaced leak-off pipes, did a bleed on the pump inlet and return lines.

Still no flow to the injectors

Re: Hello owner

Posted: Wed Feb 24, 2021 7:47 am
by Dieselman
I've not worked on an Epic system, but from what I glean the Epic pump is essentially a mechanical pump with electronic control.
There is a vane pump for lifting the fuel to the pump and providing low pressure to the internal high pressure piston pump.
The pistons are operated by a cam ring.
The start of injection is a result of the position of the cam ring timing, which has a static setting and then is refined using feedback from the needle lift sensor.
The volume of fuel delivered is controlled by the spill valve...a rapid acting solenoid valve. This spills the fuel back from the high pressure side to the internal reservoir when the required volume of fuel has been delivered.

When the engine is off the spill valve fully opens stopping any pressure and fuel delivery. In this state it is acting as the STOP solenoid.
With the ignition switched on the spill valve should be fully closed.
Once the engine is running, as dictated by the internal speed sensor, the spill valve is actuated by the ECU to deliver the correct volume of fuel.

If the pump shaft is broken it's possible for the low pressure pump to run, but not the high pressure. That looks unlikely in this case.

As you definitely have low pressure circulation it looks like the spill valve is staying open. This could be down to lack of electricity, or faulty, or just stuck open after sitting.
Using a Lexia, or scope should reveal what is happening electrically. A DMM, or just a low watage test lamp should be able to be used to see the power to the spill valve.
If the spill valve were stuck closed, all the fuel delivered by the high pressure pistons would be delivered out of the injector pipes. You might be able to jury-rig that as a test. Only perform this with the pipes disconected, otherwise the engine will run away due to be delivered an unregulated volume of fuel.
The spill valve operates exactly like a Hydractive valve. The electrical solenoid operates the Pilot valve, which then acts hydraulically on the Main there is a possibility the main valve is stuck due to lack of use, even if the Pilot valve is operating.

Check the electrical side of the Epic system, read the codes, switch on the ignition and try giving the spill valve a sharp tap with a light hammer.
Your car may be fitted with an inertia switch , which will cut the engine if tripped.

Please see attachments.
Denso Epic overview.
Gabor's circuit diagram, which covers the Epic system pages 6-8/116.

Re: Hello owner

Posted: Wed Feb 24, 2021 4:57 pm
by Stickfinger
Cheers.....some work to do there then :).....I am still sure this will work out.

Did check the ignition relay today, it is not clicking on key-turn....I tested another relay, no the system is not switching the ignition, ?? hence no pumping to the injectors but with good return-flow when turning over. ??

Suspecting ignition switch now ??

Re: Hello owner

Posted: Wed Feb 24, 2021 5:49 pm
by White Exec
If at all similar to the Bosch pumps, if the engine (ie the pump) turns over, the vane pump will bring up fuel, and if the pump chamber is already full, the excess will get returned to the tank. The Bosch stop solenoid, sfaik, prevents the high-presssure injection side of the pump from outputting, and does this immediately power is removed.

Did you check the Inertia Switch, if fitted? It was deleted from late diesels, but you might have one.

Re: Hello owner

Posted: Wed Feb 24, 2021 6:05 pm
by citroenxm
It hasn't got one. The problem here is the covering over the so called stop solinoid because it has a keypad..

The keypad is removed enabling an unlocked imobilser on the pump.. So issue is lack of power to somewhere.. As itd been found the ignition relay isn't energising.

Re: Hello owner

Posted: Wed Feb 24, 2021 7:12 pm
by White Exec
Looking at Gabor's circuit for Engine, 2.1
How are the two supplies to #807 Injection Relay....
- permanent Batt+ to pins 15,8,14,11, via F31
- + to pin 2, via IGN sw
Are both present?