Engine misfire

[Steve_B]

My wife’s 206cc (1.6 petrol 53 plate) developed a bad misfire (when I first heard it I decided to tow her home rather than drive). It also caused the anti-pollution cat warning on the dash.

An internet search shows this to be reasonably common but remedies seem to be varied, often temporary, and sometimes bizarre; nonstandard radio, turning the side-lights on and off, not using supermarket fuel.

Plugging in the laptop comes up with a P1336 error code. I have cleared and re-read the errors a couple of times and once it also came up with a P0341 error, but after clearing this has not come back.
Back in the garage the engine mostly starts and will run at higher revs (doesn't sound right though) with no load but cuts out if I back off the throttle.

I’ve looked at the plugs, which although showing signs of aging are OK. I’ve also removed the crank position sensor and cleaned the end. I can't see any leaky pipes or broken/disconnected cables either.

The fault developed suddenly and 24hr previously the car had passed its MOT with no problems or advisory on emissions and the only recent work done was a new exhaust (mid-section) a couple of weeks ago.

I’ve uploaded a couple of screen grabs from the scan with a bit more information. The main thing that sticks out to me is the low voltage on oxygen sensor 1, but this is maybe a symptom rather than a cause, which I suspect the dashboard warnings are too. Also is the 34 degree timing advance right? I’ve not been able to find any information on this (yet)

The P0341 error code is puzzling as I’ve not been able to locate a cam position sensor. However, I presume some device, possibly the coil pack, may send a signal to the ecu to simulate the presence of a sensor.

At the moment I suspect the coil pack but wondered if anyone had any other suggestions.
Thanks and I’ll update with any developments and solutions.

[Steve_B]

Just to update. I bought a used coil pack off ebay for £20. This has cured the problem.

[GrandadMonkey]

RESULT! Well done Steve. Just a thought, Peugeots don't seem to like anything other that Bosch or Peugeot branded spark plugs. So if you do renew them do bear that in mind. Best wishes.

[Steve_B]

Just to add a little bit more information. I have been asked (off the forum) why I didn’t suspect the crank/cam sensors as these are mentioned first on the fault code.

As stated in the previous post the engine doesn’t seem to have a cam sensor, so it can’t be faulty. While I don’t know too much specifically about the Peugeot ecu, I would imagine like many others the rev counter picks up its signal from the crank sensor. As I was getting a steady reading on both the dash rev counter and the scanner I eliminated that as a problem.

I took it off and gave it a clean simply because it took 5 minutes and didn’t cost anything, but to be honest I would have been surprised if it had changed anything.

I hope this might be some help to others in the future.

Interesting tip about the plugs. Looking back through my records, I used some NGK LFR6B plugs on a previous 206cc with no problems.

[gazza82]

On the subject of codes, we got one saying one of the lambdas was faulty but it didn't say which one ... Pre or Post cat.

Then the exhaust snapped at the rear join .. Nothing wrong with the lambdas ... Just a very rusty and, as it turns out, holely exhaust.

Reading codes helps but it isn't always the end ...

[GrandadMonkey]

When I started we didn't have codes. You used your eyes, ears, your instinct and eventually your experience. Most technical bit of kit I started with was a strobe light for setting the timing. Oh, and a color tune plug for setting the carburettor mixture up.

[Steve_B]

Looks like this might turn into an “oldies” reminiscing thread.

I remember the colour tune plug and I’ve still got the Gunson gas analyser but not used it in the last 20 years.

[Capncol]

I got my timing light and dwell angle meter out for the first time in years a couple of weeks ago. 1969 MK2 Jag needed setting up.