1.4 HDI error codes P0098, P0489, P1351

Hi and thank you for adding med to this great forum.

This is my first post

My old faithful Citroen C3, 1.4 HDI from 08 has started to complain.
I have read out the following error codes with ODB II as "Status: Confirmed"

P0098 - Intake air temperature (IAT) sensor 2 - circuit high input
P0489 - Exhaust Gas Recirculation (EGR) system - circuit low
P1351 - Ignition Coil Control Circuit High Voltage

I have now experienced 2 times that the engine loses the ignition completely while driving, as if someone pressed a stop button. Subsequently, the engine spins fine when the key is turned, but it shows no signs of wanting to start again.
The one time I was able to start the car again after 15 minutes and with the engine light constantly on.

When the car is running, it runs fine, I don't experience the typical EGR errors, i.e. no lack of acceleration, no rough idle, etc.
The only thing there is a distinct nod at very rare occations, as if the ignition is cutting out for a split second.

Can you point me in the right direction before I go about replacing sensors all at once?

Thank you for your help

Hello

The problem with using a generic scanner is the descriptions of the faults can be incorrect.

Your generic OBD says 'P1351 - Ignition Coil Control Circuit High Voltage' but there are no ignition coils on a diesel engine. The P1351 on a diesel is glow plugs. You can safely ignore the P1351 as this is not relevent.


When you get a situation that is like the power plug being pulled the codes are less important. You may even find you can clear those and they are not relevant to your fault. Disconnecting the electricity to the engine ECU will stop the engine and no codes are stored for that (no power, no codes). You can get old or historical codes read or they are stored when the power comes back on in an unusual way.

Check that the earth straps are good and that the main electrical power supplies and cables are good. It does sound like there is a main power feed failure, intermittently cutting the volts.


Clear your stored codes, P0098, P0489 & P1351 and re-read for fresh codes should it happen again.

Thank you for your answer.

I have gone through all of the earth straps I can find and checked plugs and connections, all seems to be fine.
I also went to a mechanic with a MaxiDiag pro tool, he read out error P0238 (Turbo pressure signal) and P0098 (AIT sensor) and also said I should check my Crankshaft position sensor?

MartinN wrote: ↑Fri Aug 05, 2022 8:25 am Thank you for your answer.

said I should check my Crankshaft position sensor?

Not easy to 'check'. Some times they have been visibly damaged. Other times it just needs unplugging and plugging back in again. It would be safer to just change it for a new one if you wanted to be sure and cross it off the list.

But with no codes for crankshaft, the mechanic is using their experience to diagnose the problem which goes beyond what we can see on the page.

Sorry for not replying to the thread before now, but simply haven't had the time...

I have purchased the Lexia tools so I can get the correct error readouts.

I found a damaged wire at the MAP sensor, this has been fixed and I also replaced both the MAP sensor and the Air Intake Temp sensor.

Since fixing the damaged wire I have not had any cutouts at all, so it seems to have fixed this part of my problems.

BUT the engine warning light is on constantly and the Lexia report error codes P0098 and P0238.
As I understand it those 2 errors relate to the AIT sensor and the MAP sensor.

Can you guide me in any directions from here?

BUT the engine warning light is on constantly and the Lexia report error codes P0098 and P0238.

Can you screen shot each of the lexia codes (not a phone picture) and add them following these instructions

Thanks for the nice clear lexia screens.

Is it possible to erase those two codes and do they return?

C3CAR wrote: ↑Sat Oct 15, 2022 2:06 pm Is it possible to erase those two codes and do they return?

No it's not, lexia can't erase them.

If the codes won't clear on Lexia, it is because the ECU is still detecting the fault.

The code is flagged, even without the engine running. This would indicate a wiring fault or bad sensor.

The descriptions given by the lexia codes you posted indicate there could be wiring issues. Check for the missing signal, check for short and open signal lines, try another sensor to prove that.

You had one faulty wire, could there be more? There should have been no damage to the loom, but you found some. This is not that common for the wires to fail. so is there something about that car? Has is got a history, what caused the damaged cable you found and could it happen elsewhere on the car?


SEDRE software (eBay link) can help show the wires for these signals and power right back to the engine ECU.