Citroen C2 1.1 Idle Misfire [SOLVED]

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Citroen C2 1.1 Idle Misfire [SOLVED]

Post by Dibber »

I have a Citroen C2 1.1 I recently bought that has an irritating idle misfire.

The back story to me getting the car is a friend who had been a PSA technician for over 35 years bought the car from the dealership he worked in just before retiring.

The car had a broken timing belt and he had to replace 4 exhaust valves on it.
I bought the car from him after it had been fixed.

The problem I have is it misfires only at idle and is at it's worst when fully warmed up.
Diagnostics show no error codes. Using live data graphing the only thing I see is wild fluctuations in the spark advance as the misfire occurs. It fluctuates between 7 and 30 degrees as the misfire occurs. That could indicate an ignition problem or the ecu trying to compensate for another issue. Fuel trims are well within accepted tolerances. Currently the long term fuel trim is sitting at 1.5 percent.

First thing I tried was setting valve clearances followed by a compression check. All cylinders bar one produced 210 psi. The other one was 205 psi.

I looked for vacuum leaks initially and thought I had found the problem as an injector seal was drawing air. New seals were fitted to all injectors and injectors resistance checked, plus I flushed them all with carb cleaner.

All that made no difference to the misfire.

Next I replaced inlet the manifold gaskets as a matter of course though a smoke test did not reveal any issues. The throttle body then had a clean.

As coil packs seem to be a common issue I decided to replace mine and put in a fresh set of Bosch plugs. The original coil pack was a Sagem and I replaced it with a Bougicord.

No difference at all..

I then decided to clean all the engine earths and tried swapping out the MAP and crank sensor with known goods and the upstream lambda. Again the misfire remained. I even checked the flywheel reluctor ring when the crank sensor was out. Cam timing has also been checked.

The misfire is never bad enough to cause it to stall and I have been unable to identify if it's on one cylinder. Plug colours are all even. I did the screwdriver on injector test to listen for any differences in injectors. All appear to be equal with no noticeable drop out. The misfire I would describe as random but frequent. It's occurring every few seconds.

I cobbled up a fuel pressure gauge to the fuel rail. Due to leaks I have been unable to do a running test but a key on prime indicated 3.5 bar. I am awaiting delivery of fittings to conduct a running test.

Most recently I changed the coolant sensor but still this issue remains. I have checked plugs on engine wiring for corrosion including Ecu but it all appears to be in good shape.

I probably have forgotten other things I have done as this has been going on for three months. Hours of research but I have learned an enormous amount.

I know these TU engines are archaic but I don't believe they would be that rough on idle or are they? Does anyone know if it's normal for the throttle body to produce a buzzing noise with ignition key in first position?

The friend I bought it from is not that knowledgeable when it comes to the electronics so he has been unable to assist.

Any suggestions would be appreciated from forum members.
Last edited by Dibber on 11 Apr 2019, 12:26, edited 1 time in total.

Hell Razor5543
NOT Alistair or Simon
Posts: 10492
Joined: 01 Apr 2012, 09:47
x 983

Re: Citroen C2 1.1 Idle Misfire

Post by Hell Razor5543 »

Hi, and :welc: to the forum. While I am unable to help directly, there are two things I would suggest that may allow others to help you out. First, post up the VIN (don't worry about security on this; it will be automatically obscured, but Moderators will be able to read it) so as to get the correct details for your car, and second, see if you can get her on a Lexia, read off any error codes, note them down, clear them, run the engine for a short while, and then check for errors again. If there are any codes after this post them up here, as they may well help nail down the problem.

User avatar
NewcastleFalcon
Posts: 11641
Joined: 25 Feb 2009, 11:40
x 1021

Re: Citroen C2 1.1 Idle Misfire

Post by NewcastleFalcon »

You appear to have methodically investigated the usual suspects. From first hand experience I know that worn cam lobes can cause erratic idling. It was not your model of car, but replacing camshafts and giving the hydraulic cam lifters and rockers a good clean, lube and replace as necessary worked in my case.

May have been some damage to the your camshaft(s) by the previous timing belt failure.

Regards Neil
Last edited by NewcastleFalcon on 20 Mar 2019, 00:37, edited 1 time in total.

User avatar
white exec
Moderating Team
Posts: 6080
Joined: 21 Dec 2015, 13:46
x 1013

Re: Citroen C2 1.1 Idle Misfire

Post by white exec »

Fluctuation of spark/ign timing - crankshaft position sensor, or connection to it?

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Re: Citroen C2 1.1 Idle Misfire

Post by Dibber »

Thanks for the welcome James. I will get my VIN later today and post it.
I take it you mean using Lexia to get manufacture specific fault codes?

I currently don't have access to Lexia but one of the things I have done is to get Diagbox and Sedre up and running on my laptop. I have been trying to figure out who best to buy a diagnostic head from. The website mentioned on the forum does not have any last time I checked.

NewcastleFalcon thanks for that suggestion. It has been something I considered and I did try to inspect the cam lobes and roller rockers when doing the valve clearances. Due to the setup of the cam and rockers it's actually quite difficult to make a proper inspection in situ. The cam is actually located on the head with the cylinder head bolts. Removing them would probably involve having to replace the head gasket..

I am not ruling it out, however the engine seems to run quite well beyond idle. I guess I could rig a dial gauge up to measure valve lift without removal of head to be sure. I was able to check the rollers in place and they were absolutely fine. If a cam lobe had worn I would have expected to see wear marks on the corresponding roller.

White exec thank you also for your suggestion. I have fitted a new crank sensor. Wiring is something that I have to consider definitely.

Further research into the wild fluctuations I am seeing led me to an American tuning forum last night. It appears as I may have mentioned in my original post that wild fluctuations are the ecu trying to correct and stabilise the misfire. Those guys were talking about programming ecus with performance mods in great detail and what parameters to change to try and achieve a smooth idle.

Taking stock of everything to date my next step is going to be a fuel pressure check at idle. I also want to get Lexia up and running. I have been unable to find out what level of live data Lexia can produce. Ideally I would like to find out spark durations, misfire counts and injector durations and corrections. Maybe also clear adaptations. If anyone is familiar with Lexia it would great to hear if any of those are possible.

I am absolutely determined to get to the bottom of this. I am a bit of a perfectionist which can be a burden at times :rofl2:

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Re: Citroen C2 1.1 Idle Misfire

Post by Dibber »

VIN Number is VF7**************[VIN obfuscated, can be read by forum staff]

User avatar
GiveMeABreak
Forum Admin Team
Posts: 20417
Joined: 15 Sep 2015, 19:38
x 2018

Re: Citroen C2 1.1 Idle Misfire

Post by GiveMeABreak »

For the benefit of those contributing to this issue, the OP has a C2 3 Door Saloon 1.1 i 60 (TU1A) with manual gearbox 5.

I suspect there may always be an issue after damage of this type (possibly hidden), but 10/10 for Percy Verance :wink:

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Re: Citroen C2 1.1 Idle Misfire

Post by Dibber »

Percy Verance and I are long time acquaintances. You may well be right. I saw the four exhaust valves that were replaced and they were visibly bent. I can see me pulling the head off yet. Oo err missus.

User avatar
NewcastleFalcon
Posts: 11641
Joined: 25 Feb 2009, 11:40
x 1021

Re: Citroen C2 1.1 Idle Misfire

Post by NewcastleFalcon »

Dibber wrote:
20 Mar 2019, 12:01
I am not ruling it out, however the engine seems to run quite well beyond idle.


That was exactly the same in my case. Running at anything other that idle revs, the engine performed as normal with plenty of poke. Slow down and sit stationary at traffic lights and it would idle roughly and throw up some misfire codes if you didnt "keep the revs up".

Regards Neil
Last edited by NewcastleFalcon on 22 Mar 2019, 10:13, edited 1 time in total.

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Re: Citroen C2 1.1 Idle Misfire

Post by Dibber »

Thank you Neil, that is very interesting to know. I will definitely look into that. I think I saw some cam data within Service Box to reference off.

User avatar
xantia_v6
Forum Admin Team
Posts: 7383
Joined: 09 Nov 2005, 23:03
x 407

Re: Citroen C2 1.1 Idle Misfire

Post by xantia_v6 »

I know that it is a different engine, but take a read of viewtopic.php?p=570212#p570212 which has two cases of cam lobes twisting in fabricated camshafts as a result of timing belt failure. I don't know the construction of your camshaft(s), but worth thinking about.

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Re: Citroen C2 1.1 Idle Misfire

Post by Dibber »

Today whilst driving I noticed another issue that might possibly be tied into my misfire. I have only had the car on the road for a week so I am still getting tuned into how it runs. Anyhoo.. earlier in the week a couple of times as I drew to a halt the revs would drop to idle then bounce back up to about 1100 rpm. I thought it was my foot hitting the accelerator pedal at the same time as I was braking..

Today I discovered it's got nothing to do with that. The engine appears to fall to idle and bounce back up to 1100rpm then fall again. Sometimes this happens two to three times before it finally settles.

I think this might be related to the misfire but am at a loss to explain it. Fuel issue? Maybe something to do with the fuel regulator? Vacuum leak possibly but I have done several tests and found nothing.

Thanks xantia I looked at that post. Pressed on cam lobes!! I will see what I can find out in respect of it. Thanks.

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Re: Citroen C2 1.1 Idle Misfire

Post by Dibber »

Well it turns out there are a few manufacturers that produce lobes that are fitted onto a shaft. The hid engine is one of them. I have found no info though on the TU engines as to them having that design or not.

It should be easy enough to visually see what type of cam it has. I will pull the rocker cover off tomorrow and eyeball it plus give all the rocker gear a good look over while I am at it.

User avatar
GiveMeABreak
Forum Admin Team
Posts: 20417
Joined: 15 Sep 2015, 19:38
x 2018

Re: Citroen C2 1.1 Idle Misfire

Post by GiveMeABreak »

This is the parts diagram of the Cam for your C2: Part 0801W3 in case it helps.
C2 Cam.PNG

Dibber
Posts: 56
Joined: 19 Mar 2019, 11:26
x 4

Re: Citroen C2 1.1 Idle Misfire

Post by Dibber »

:wave2: Thanks Marc. I was looking at that earlier as I have Service Box myself. Appreciated though.