Repeated failed forced regens - limp mode

[Sheffy]

Hi,

I have a doblo 223 1.9 multijet. It is is limp mode and I'm trying to regen the DPF but it fails and says Injected quantities out of permitted range".

What does this mean?

I've got no EML on, only code is glow plug relayed (P0683) but I'm still stuck in limp mode.

Anyone have an idea?

[shpuncik]

usually glow plugs system should be working without errors to be able to run DPF regeneration

[Sheffy]

usually glow plugs system should be working without errors to be able to run DPF regeneration

So you think the glow plug fault could be contributing to failed forced regens? I'll replace the set if so.

[abarthmultijet]

Yes, you should certainly replace the glow plugs first! They are not expensive and easy to replace (with a bit of experience). Make sure they are the right voltage.

[Sheffy]

Yes, you should certainly replace the glow plugs first! They are not expensive and easy to replace (with a bit of experience). Make sure they are the right voltage.

Thank you. I've ordered a set and will update once I've fitted and tried to regen again.

[s130]

While you are waiting for the plugs to arrive soak the old ones around the base/thread area with penetrating fluid. Go gently when removing as too much force will sheer the tops off! If tight then try a fixed wrench and repeatedly tap / shock / jiggle.

[abarthmultijet]

While you are waiting for the plugs to arrive soak the old ones around the base/thread area with penetrating fluid. Go gently when removing as too much force will sheer the tops off! If tight then try a fixed wrench and repeatedly tap / shock / jiggle.

Exactly, make sure you don't cross thread the new plugs, the aluminium head is soft and the threads are easily damaged. If the plugs are really stuck try to get them loose them with a hot engine.

[Sheffy]

So replaced glow plugs and no fault codes remain. No coil light now and no EML light. However the car is still in limp mode.

Tried to do a regen on multiecuscan and it failed again. It states generic error in the status. "injected quantities outside permitted range". DPF pressure is reading 14mbar at idle, 88+ at 3500rpm. Sound too high?

Has anyone got any ideas why it's in limp mode with no fault codes and also why the DPF regens keep failing?

Thanks

[abarthmultijet]

Did you make sure the following conditions are right?:

- engine temperature >70 degrees celcius (90 degrees best)
- Vehicle stationary and handbrake on
- clutch and brake pedal released
- Engine idling (850rpm +/-50rpm)

[Sheffy]

Yes the car was meeting the requirements to start the procedure and it does start the dpf regen without issue.

It initially revs up to 2000rpm and then once the EGTs are up it then revs to 3500. Once the EGTs reach 400°c, the car starts to vibrate/rumble slightly and the differential pressure climbs from 80mBar to 150+ and then the regen fails. It shows 0.00% completion, "generic error" in the state and a box comes up which says "injected quantities outside permitted range".

My mechanic has just drilled a hole through the DPF and we will try a forced regen again soon.

We are running out of ideas.