Misfire and stuff on 04 C5 2.0i (not hpi)

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NewcastleFalcon
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Re: Misfire and stuff on 04 C5 2.0i (not hpi)

Post by NewcastleFalcon »

....yet another unproductive contribution from me, other than a supportive aside in a "share the misery" sort of way.

Have a read of this thread. One of the "fleet" which I look after has the exact problem....bit different to yours.... goes like stink throughout the rev range, but at tick over fuels too rich, stuttters and stumbles and throws up the dreaded misfire codes.

I have read loads of unresolved threads on the problem, which in the good old SU Carburettor days would have been rectified in 10 seconds flat, but seems incapable of resolution by the finest brains on the internet, and most definitely "main dealer" finest brains whose final recommendation of the "it could be that so we will replace it approach" is usually "engine replacement" :-D :!:

I will offer a bit of an answer to one of your questions, and I could of course be 100% wrong, O2 Bank1 Sensor 2 would have no effect at all on your misfire. Its downstream of the Cat, and may get its trouble code thrown up as a consequence rather than a cause of the misfire.

So in conclusion I watch this thread with interest, and wish you well, but hopefully more knowledgeable members will be along with more practical advice. I did see a thread which Simon (Mandrake) contributed to recently with a logical method of investigation into such problems, rather than replacing bits which could be the cause at random.

All the best

Neil
Only One AA Box left
687 Trinity, Jersey
deian9
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Re: Misfire and stuff on 04 C5 2.0i (not hpi)

Post by deian9 »

Thanks neil.
I tend to wonder if they are related too. I'll clear faults, disconnect that O2 sensor, ane try to run without it. But since they share a common earth, along with whatever else that causes it to throw up possibly a phantom fault before the real problem is revealed.

The only other thing it could be is the ecu signal outs to the injector.
I wish I had an oscilloscope.

The problem is, the car itself resembles an electronic circuit, so any fault in something echoes down an earth to show a fault in something else.

I wouldn't mind my mechanically pumped zx diesel now. I'm gonna buy one.
deian9
Posts: 36
Joined: 07 Dec 2016, 09:39
Location: Liverpool
My Cars: 2004 C5 2.0i Exclusive

old ones in no particular order
Xsara HDi 110 auto
Xantia HDi 110 manual
Xantia V6 auto
Xantia 1.9td manual
XM 2.0i auto
ZX 1.9tdi manual
Xantia 2.1 manual
Pug 106 1.5d
Mercedes Benz C250TD
BMW e30 325i Sport manual
BMW e30 325i SE auto
x 2

Re: Misfire and stuff on 04 C5 2.0i (not hpi)

Post by deian9 »

It's definitely related to the suspension fluid, or with it being low, doing citrobeotics seems to cure it, not sure how, air seems to build up in the resevoir, but there is a sensor on the hydraulic pump that goes into the engine loom... any explanations?

edit... at least temporarily, but it definitely seems to affect it. had a good stint to blackpool just now, it drove well 70% of the time, weird.
deian9
Posts: 36
Joined: 07 Dec 2016, 09:39
Location: Liverpool
My Cars: 2004 C5 2.0i Exclusive

old ones in no particular order
Xsara HDi 110 auto
Xantia HDi 110 manual
Xantia V6 auto
Xantia 1.9td manual
XM 2.0i auto
ZX 1.9tdi manual
Xantia 2.1 manual
Pug 106 1.5d
Mercedes Benz C250TD
BMW e30 325i Sport manual
BMW e30 325i SE auto
x 2

Re: Misfire and stuff on 04 C5 2.0i (not hpi)

Post by deian9 »

It's still there... Going to try a battery swap soon with someone.

The faults, including the engine light and the service lights were off last night and this morning. Now they are back. Then the radio sounded 'better' after a slight crackle, as if the amplifier got powered up.

It now seems like I'm making stuff up and chasing ghosts, but I swear I not. I feel like I'm hallucinating this stuff up, but I'm not.

Seriously though, what a badly designed electronic system this car has, how can so many people (a team of developers at PSA) fluff if it up so much?
wheeler
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Re: Misfire and stuff on 04 C5 2.0i (not hpi)

Post by wheeler »

deian9 wrote:
Going from the wiring diagram an O2 sensor and an injector shares the same earth point .
Surley the injectors are earthed by the ECU ?
The injectors should have a live supply & the ECU pulses an earth to operate them.
deian9
Posts: 36
Joined: 07 Dec 2016, 09:39
Location: Liverpool
My Cars: 2004 C5 2.0i Exclusive

old ones in no particular order
Xsara HDi 110 auto
Xantia HDi 110 manual
Xantia V6 auto
Xantia 1.9td manual
XM 2.0i auto
ZX 1.9tdi manual
Xantia 2.1 manual
Pug 106 1.5d
Mercedes Benz C250TD
BMW e30 325i Sport manual
BMW e30 325i SE auto
x 2

Re: Misfire and stuff on 04 C5 2.0i (not hpi)

Post by deian9 »

I think I missed that detail. I think I saw and assumed it was the other way round. Maybe you are my saviour. Thanks for that suggestion. Maybe I've been looking for this problem the wrong way round.
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