1999 2.0 16v Petrol Misfire - Fullchat
I own a 1999 406 with a 2Ltr 16v petrol engine. I have noticed that at around 70 MPH, when there is no load on the engine, a slight intermittent hesitation. I've changed the plugs twice, used some injector cleaner and use only branded petrol even trying Optimax. - No difference.

Much against my better instincts booked it in at the main dealer. Charged me £50 for a diagnostic check. Said they found evidence of shorting from the coil ( on this engine the coil and plug caps are in an integral unit that sits over the plugs.)However they cleaned it and stated that if the problem persisted then the coil would have to be changed.

The problem is still there and I changed the coil (£88.83)!
And guess what? Its still there. Seems even with all the latest technology it can be still a struggle to diagnose faults.

Anyone any experience of this engine or like to take an educated guess? I'm stumped.


Edited by Dynamic Dave on 03/12/2009 at 12:39

Pegeuot 406 Petrol Misfire - Ben79
i don't know what is wrong with your car, did the dealer try an ECU software update? Try looking on the alt.autos.peugeot newsgroup.

Pegeuot 406 Petrol Misfire - Andrew Moorey (Tune-Up)
Possibly the oxygen sensor playing up if high mileage.
Pegeuot 406 Petrol Misfire - Fullchat
The car has done 43K. Where is the oxegen sensor?

Pegeuot 406 Petrol Misfire - lezebre
Hmm, that's not high mileage. fyo the O2 sensor, aka lambda sensor, is your on-board exhaust gas analyser. It is sometimes found in the front pipe, where it has been known to be disconnected by fast-fit emporia, or more usually in the manifold.
Pegeuot 406 Petrol Misfire - Fullchat
Does'nt time fly, didn't realise but its exactly a year since I posted this problem!!!!!
Anyway now the planning stage is over it was time for action. havink tinkered with other bits and bobs the lambda sensor was looking hot favourite.
Visited my local Peugeot dealer and asked for a replacement sensor. Usual story "We can get you one" 90 something £ + VAT.
However he then made a quick telephone call to there new 'Fastfit' depot which specialises in Motoquip parts. As a result I went to see them just before 5pm and although they did not have one in stock they ordered one for next day (Sat) and it duly arrived. Price of the Sensor - less than 40 quid although I had to buy an adaptor wire to join the Sensor to my loom. £54 in total.
And it seems to have cured the problem!

Pegeuot 406 Petrol Misfire - carldenman

I know its been a while since you posted, but i too have a similar problem with my 1999 2.0 16V Peugeot 406. ( uneven / lumpy running at tickover, and slight misfire during normal driving... but sometimes it can be fine ) Can you confirm if the Lambda sensor did finaly cure your problem and if so, where did you purchase it. Any feed back would be graet, as i too have been down the route of changing plugs, checking coil packs ect ect

Kind Regards
Pegeuot 406 Petrol Misfire - ca2blue
Sounds very similar to a problem I had the day after having a dealer fitted exhaust. Managed to "limp back" to the dealer who subsequently found a "loose wire" on the lambda sensor. No charge and no appology.........I now use an independant Pegeuot garage.
Pegeuot 406 Petrol Misfire - carldenman

My problem still continues, the MPG is around 30/31 which seems very low to me, as i was expecting around 36. i have been trying to resolve this problem for over a month. Coil pack has been replaced, plugs, injection filter,Air Filter, MAP sensor,even removed and thoughly cleaned the throtle housing and idle valve. Checked TPS switch, CTS also seems to work fine. Any one got any more ideas, my car is the EW10 engine,
Cheers Carl
Pegeuot 406 Petrol Misfire - PugHPi
Did you have any look Carl...

I'm also an unlucky EW10 owner... with a similar fault... 30-31 MPG sounds about right to me not sure I've ever had much more than unless on a long run.

Do you know what Fault cod eyou're getting off the engine?
Pegeuot 406 Petrol Misfire - Smoggie1
am having similar problem, 1999 / 406. 2ltr petrol
started missing a few weeks ago, advised to get a coil pack which i did 2nd hand , problem still there, yesterday the car seriously loses power and starts loud banging/misfiring through exshaust, towed to garage and they put the old coil pack which i still had back on and that cured the serious backfiring and power loss, went and got another coil pack from breakers, fitted and the problem of misfire is still there, new plugs fitted, still misfiring.
of note i had a new back and middle box fitted a few weeks ago and the exhaust sounds like its blowing badly, took it back and not blowing just extremely loud, could this be related to the problem, as the engine management light is not coming on the computer is not tracing any fault, does this mean it wont be the lambda sensor??
am at a loss here.