1.4 16v hdi poor running after injector change

C3 1.4 16v hdi 8HY

Hi everyone, I've changed an injector ( Delphi) on my wife's C3 and coded it into the ECU I also cleaned the egr (quite clean already)
and the egr pipe at the manifold end it was choked up to a 13mm dia hole through the gunge but cleaned up well. I only moved or
disturbed the egr and pipe,
metal injector feed pipes on 1 and 2 injectors and no; 2 injector.
I primed the fuel system with the plastic bulb and when it started the engine was fairly lumpy on tick over, slow and hesitant to accelerate
it sounds a bit tappety It threw up p0401 so I blanked off the egr and cleared the code,
it then threw up p0402. I checked all the pipes to the two solenoid valves
and all ok, it seemed to be the solenoid to the egr. so swapped the egr and turbo valves over, cleared the code and it stayed clear.
The engine started easier and wasn't so lumpy, it also better at accelerating and smoother and still tappety but still not right.
I swapped the valves back again the codes have not come back, but the engine is no different. I've done a leak off test and all 4 injectors
are giving the same levels including the new 1. the Haynes manual mentions " reinitialising the engine ECU. While road testing, engage
third gear and stabilise the engine at 3000 rpm, then accelerate fully up to 3500 rpm" can anyone confirm this or give same guidance

Regards Ian

Hi Ian, what was the reason for changing an injector?

How was the engine tapping noise and performance before the injector change

Was it a new injector or a recon with a new coding number?

Hi C3CAR,

1
About 12 months ago it was hard to start and threw up codes p0202 ( injector circuit short to earth or short to positive) and p1163
( permanent fault. no resetting by accelerometer). I couldn't clear the codes so checked the injector loom, multi pin plug at the top rear
of inlet manifold, nothing looked corroded, damaged or broken. I removed the injector loom and checking the various circuits found 1 of
the wires into the plug when twisted would break the circuit. I swapped the loom from my car and ordered a new plug. I left my loom on
her car, repaired her loom and fitted hers to my car.
The wife's car ran for about 6 weeks without problem then threw up the same codes
the weather wasn't good but I found that using a thin screw driver and levering against the manifold I could wiggle the electrical plug
under the leak off plug and could then clear the codes, this time it stayed clear for about 4 weeks, at this point I left my maxi scan in
the car permanently so my wife could clear the codes if it happened while on her own as the time between the codes flashing up
got less and less so I swapped the looms again. I could tell when it had "tripped out" as it would sound a little tappety
all was fine then the cycle started again. I removed the plug from the injector again, 1 of terminals in the injector was dull compared to
the other, using needle files I cleaned this terminal and applied a small amount of conductive grease, this worked great for around
2 months, in between doing all this I still checked all the contact points for the electrics and checked the looms almost to the ECU
it keep coming back to the injector. in this time my car, regardless of which parts were swapped always ran fine.
It seemed like the injector would trip out but wiggle the connector and the codes would clear and run sweet, we then decided to change the
injector.

2
Apart from having to clear the codes and the " tappety" sound it ran very well and no noisier than mine.

3
Its a new injector and coded in with Lexia.

With regard to the Haynes manual saying to " initialise the engine ECU " is this required? I would say its running on 3 cylinders but not
rough enough to actually be running on 3. I should try again with the Lexia but I don't think my brain will let me keep up.

I could try the loom from my c3. Unfortunately my 1.4 16v hdi the ECU spiked and corrupted itself and couldn't be repaired so I bought
a 1.6 16v but I did keep some parts off the old one.

Many thanks for your reply
Kind regards Ian

chipmonk1212 wrote:With regard to the Haynes manual saying to " initialise the engine ECU " is this required? I would say its running on 3 cylinders but not
rough enough to actually be running on 3. I should try again with the Lexia but I don't think my brain will let me keep up.

I will have another look at you post soon, but for now, I am not aware of a need to " initialise the engine ECU " if you change an injector. Its not been mentioned before and I have not see it in the lexia screens of information on how to complete tasks.

I am also not aware that the engine ECU is a learning ECU, unlike the semi automatic gear box one.

Did you code the correct injector in lexia? They may not be numbered the way you think?

Will it do any harm to do the haynes suggestion? They may be giving you a hint

Hi, when I removed the injector I checked the number against the list on Lexia which corresponded to number 2, I then replaced that number
with the number on the new injector, number two piston working from the flywheel.

Ian

chipmonk1212 wrote:Hi, when I removed the injector I checked the number against the list on Lexia which corresponded to number 2, I then replaced that number
with the number on the new injector, number two piston working from the flywheel.

Ian

Great. No problems there.

There is a topic showing how to improve worn connectors on the ECU loom connectors which may be useful if you know which ones are for the injectors.

citroen-c3-tips/improving-poor-ecu-plug ... t1781.html

If everything else has been checked and even changed, what can be left?

Hello C3CAR,
I finally have an update.

I tried the method described in the Haynes manual and can confirm it doesn't work.
I swapped the injector looms again but threw up a code to the maf, checked all the circuits on the loom with a tester but couldn't
get a reading on number 4 pin no matter how I twisted or bent the wiring loom, changed the loom back and no codes I tightened as many
connections as possible to the ECU plugs and the round plug above the inlet manifold, no different. I then changed the injector back to see
if the new injector was duff, again no change. I removed and checked all the vacuum pipes, renewed the air and fuel filter despite having
done only4500 miles.
took it for a test drive and the change was immediate, so appears coincidental it played up when I replaced the injector. I always change the
filters around 10,000 miles and guess either a bad filter of bad fuel but I'll keep monitoring them.

Thanks for your help and thought the update might be of benefit, I notice a lot of the posts end with no outcome just a big ?
Kind regards Ian

chipmonk1212 wrote:I swapped the injector looms again but threw up a code to the maf,

There can be MAF codes and the car still runs OK. Do you recall which MAF code it was?

chipmonk1212 wrote:Thanks for your help and thought the update might be of benefit,

Yes, thanks.

chipmonk1212 wrote: I notice a lot of the posts end with no outcome just a big ?

This is a bit of a problem. Some older cars get scrapped and I assume others get fixed by a garage and there is only a bill and no information about how they actually fixed it? I have heard of some that get sold on or traded in.

Hello C3CAR,
I'm not sure but think the code was P0104, but as I there was a break in the wire somewhere I just swapped the loom back
Just 1 thing less to think about but sure the fault was the loom not the maf.
as for the lack of feedback from some posts, as you say they're sold on, scrapped or pay a bill they don't have the time to sort the
problem out, Its always good to know the outcome though.

regards Ian