Diagnostic and advice needed

[mihai_leontescu]

Error on screen: Engine fault. Repair needed

Error on board: Yellow exclamation triangle and the yellow engine on the bottom right of the board.

The exclamation triangle is not permanent, it dissapears after 10-30 sec and then appears again in few minutes. The yellow engine is permanent once the engine fault appears, but not before. If i let the car cool down few minutes and start it again, the error dissapears and the engine works properly. See below problem with the engine.

On the tester there are two main errors:

U1218 Red CAN intersystem that is permanent and cannot be deleted. It’s connected with the main computer/electronics and the mechanics i talked to say that it should not affect the engine while driving.

P12A2 Cylinder 1 that appears only after Engine fault appears. It can be deleted but then appears again.

After going through 4 service places I eliminated the following options (I hope):
- There are no issues with the injectors and cilinders
- The compression in the cylinders is fine
- The DPF works fine (although I havent cleaned it - car has 240k km) and the regeneration happens every 300km. There is quite some black smoke when I accelerate rapidly, maybe I can still clean the DPF?
- The usual suspects are all in good parameters: oil, antifreeze liquid, DPF liquid (tester says it has 500ml but the tank sounds empty)
- The software was also updated after asking permission from Peugeot

The main problem of this error is that the reaction of the acceleration decreases while driving and it’s unpleasant. When the engine works properly it takes 5 seconds to go from 2000 to 3000 rpm. When the engine fault appears it takes more than 15 seconds when pressing the acceleration to the bottom and very slowly increasing in speed. The sound of the engine is the same and doesn’t sound faulty.

This error only appears after about 100km when I drive long distance. So far it never appeared when driving in the city. I only have this car for 2 weeks now and I want to believe the previous owner didn’t know about this error. It doesn’t matter anymore, I need to find the magical puzzle piece to get rid of it. Please help! What would you do if you were in my shoes?

Car is Peugeot 5008 from 2013

Series of the car: VF3**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Very likely the DPF is at end of service life, so either needs a thorough and careful clean or replacement. Although it reports as regenerating, that does not mean the filter is not clogged - only that it is attempting regeneration. That would also fit in with the smoke - which there shouldn't be any. The filter gradually fills with ash, engine debris and cerine deposits from the additive that can't be burned off and eventually clogs the filter. When this filter is blocked you should be getting a message warning you, but at some point the engine ECU will go into backup mode and limit engine power if there are faults.

As for the fault code, that has quite a lot to do with affecting the engine, so not sure why your mechanic doesn't think so....

Fault Code:	P12A2
Description of Fault:	No. 1 cylinder: The injector is not injecting enough or poor cylinder compression. Description of the diagnostics Drop in torque on one cylinder identifiable by a fall off in engine speed between 100 and 200 rpm on the item concerned, the engine being stable and under load. For a period of 9,6s when the engine speed is at 750 rpm For a period of 1,4s when the engine speed is at 5000 rpm
Conditions for Fault to clear:	Idling and accelerating, not under load (Engine hot)
Downgrade Modes whilst Fault is active:	Deactivation of the traction control Performance of ESP settings impossible Deactivation of the strategy for monitoring the current of the fuel flow regulation valve Increase in the idling speed Deactivation of the kick-down control for automatic gearboxes Deactivation of the injector resetting strategy Limitation of performance Irreversible deactivation of the vehicle speed limiter (Need to switch the ignition off and then on, in order to make the function available again) Irreversible deactivation of the vehicle cruise control (Need to switch the ignition off and then on, in order to make the function available again) Switching on of the warning lamp and/or warning message: Warning lamp MIL "SERVICE" warning lamp
Symptoms:	Engine hesitating, cutting out Unwanted acceleration Noise Malfunctioning of the engine when idling Starting problem Smoke from the exhaust Lack of power
Suspect Areas:	Fuel injector 1 Inlet valve; Exhaust valve; spring; seal Piston; Segment; Shaft; Cooling Conrods Electrical harnesses

[RichardW]

It probably needs a new injector - it's common on the 1.6, less so on the 2.0. I'd be tempted to swap the No 1 injector (note this is flywheel end...!) to another cylinder to see if the fault moves.

It shouldn't smoke at all, check if there is soot in the tail pipe - if there is, then the DPF is broken or someone has messed with it.

The U1218 fault has come up many times, but I'm not sure we've ever got to the bottom of it! I wonder if it might be related to the battery protection unit.

[mihai_leontescu]

That is a SMART idea, swapping the injectors! I feel like Sherlock Holmes eliminating options and searching for new clues. I will ask the service to do it today and go for a long ride again and tomorrow I have an appointment to clean the DPF - it doesn’t hurt to do it even if the fault is not there. Can you please explain in other words why I should be careful with the flywheel end?

[mihai_leontescu]

Thank you GiveMeABreak (bear with me)!
I will focus on the cylinder error even though it doesn’t mention anything about DPF and car never complained about the DPF.
Regarding the permanent error U1218 looks like there’s nothing I can or should do, correct?

[Paul-R]

Can you please explain in other words why I should be careful with the flywheel end?

It's not that you have to be careful with the flywheel end, it's the fact that PSA number the cylinders from the flywheel end so that's where number 1 cylinder is.

[mihai_leontescu]

Got it, thanks! Haven’t heard this term before.

[mihai_leontescu]

Update: The idea to swap injector 1 with 2 was genius. I did some long trips this weekend and I didn’t receive the error P12A2 anymore! I really hope I won’t see this error again!

I also cleaned the DPF just to be sure and the car does not have as much black emissions as before. But not sure how the DPF guys accessed the filter cause now my air conditioning does not work anymore (and I fixed it 1 week ago). The freon got lost somehow somewhere. I’m really tired of these endless problems. Will need to go the service tomorrow to check the air con system.

But thank you all for the amazing ideas and prompt feedback! Love from Bucharest!

[PaulC5]

A common place for an air con refrigerant leak is the condenser at the front. I needed a new one for the C5 and a relative needed one for a Golf.