Temporary loss of power, Peugeot 406

Pugsulike · Post by **Pugsulike** » 21 Jun 2005, 02:46

I am experiencing an intermittent fault on my 2001 Peugeot 406 2.0 HDI (110). Occasionally whilst driving or upon starting the car, the dashboard display states "Engine anti-pollution system defective". At the same time, the engine management warning light comes on and stays on. The engine loses power in that it holds back and gear changes have to be made sooner than usual to maintain acceleration.
If the car is stationary, in neutral with the engine running, I can floor the accelerator but the revs will not go above 2900rpm. It is as though a rev limiter has cut in as the revs rise quickly to 2900rpm and stay there.
There appears to be no noticable pattern to this fault, which will correct itself after a short time (could be 3 miles, could be 20 miles and without warning, which can be a bit disconcerting) although the warning message and light remain on for some time afterwards, possibly a couple of days.
The car may go for 2-3 months without problem although it has occurred 3 times in a week.
The car has been to a Peugeot garage twice in the last year for the ECU (the cars 'brain') to be analysed at about £50.00 a throw, but their technicians can find nothing wrong! They just say bring it back if it happens again. Goodbye another £50.00, hello happy Peugeot accountants.
Can anybody out there help me please?
Thanks, Clive.

demag · Post by **demag** » 21 Jun 2005, 05:22

Don't suppose the Lamda could be packing up or have a bad connection?
That might give a false exhaust gas reading to the ecu.

wheeler · Post by **wheeler** » 21 Jun 2005, 05:23

what were the fault codes that came up when peugeot checked it ? without knowing that your looking at a needle in a haystack.it could be anything putting the car into backup mode from an airleak to a sensor.

hill · Post by **hill** » 21 Jun 2005, 23:59

This is not a joke reply.....
Join the AA.
If the engine management light stays on for a couple of days, next time, buy a paper and park next to a cafe or somewhere with a nice view and prepare for your half hour wait. Call them and say 'help' as you shouldn't drive with the light on etc etc. They'll plug into the ECU and tell you what the fault was. Do this once and you've saved money on the £50 garage fees and you've also got breakdown cover for the year as an added bonus.

acataldo · Post by **acataldo** » 22 Jun 2005, 00:29

I don't understand how the peugeot dealerships cannot pull up any codes. If the car goes into limp home mode the fault code should be stored and can be viewed at a later date.

samcro · Post by **samcro** » 22 Jun 2005, 18:06

Does the 406 in question have EGR (exhaust gas recirculation)?
I had problems with a slightly lower tech 106 (no electronic ECU) losing power intermittently. It turned out that the EGR activation switch (linked into the accelerator mechanism) was corroded inside and the contacts were literally loose inside the switch body. Vibration caused the bits inside to jiggle about and activate/decactivate the EGR. EGR is supposed to be an 'anti-pollutant system'.

Pugsulike · Post by **Pugsulike** » 23 Jun 2005, 00:52

Thanks everyone for your replies - it's given me something to go on. I think that part of the problem nowadays is that the garage "technicians" in franchised garages are trained more on computers than good old fashioned mechanics. If their machine doesn't tell them exactly what's wrong, they're stuck.
They said that no fault codes came up. However, last time it was in, somehow my ECU got locked up whilst they were interrogating it and then the car wouldn't start. This was on a Saturday and it took them until the following Thursday PM to sort it(!), which included fitting a new ECU (which they didn't charge me for).
By the way, I'm already with the AA, but as the car hadn't actually broken down, I didn't think of calling them.
My Haynes manual only mentions the Lamda sensor under the petrol models, but it does have EGR.
Thanks again,
Clive.

fastandfurryous · Post by **fastandfurryous** » 23 Jun 2005, 05:53

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by samcro

Does the 406 in question have EGR (exhaust gas recirculation)?
EGR is supposed to be an 'anti-pollutant system'.
<hr height="1" noshade id="quote"></blockquote id="quote">
EGR is the work of the devil. All it does is to completely choke the inlet manifold and inlet ports with the most horrid yack you have ever seen. It may well be a good idea on new cars, as it reduces NOx and SOx to some extent, but on an older car (5+ years) it causes chaos. Far more environmentally friendly to remove/disconnect/bin the EGR, and keep the car on the road for longer, thus meaning another new car doesn't have to be made, and one scrapped.
So many people, including governments, don't seem to realise that the environmental burden of scrapping one car and making another new one is massively more than the slight improvement in emissions from a new car compared to the old one.

hill · Post by **hill** » 23 Jun 2005, 23:49

[quote] fastandfurryous Posted - 23 Jun 2005 : 00:53:17
quote:fastandfurryous Posted - 23 Jun 2005 : 00:53:17
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So many people, including governments, don't seem to realise that the environmental burden of scrapping one car and making another new one is massively more than the slight improvement in emissions from a new car compared to the old one.
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Spoken like a true Land Rover owner- well said FAF

Pugsulike · Post by **Pugsulike** » 02 Jul 2005, 21:12

Hi,
Well, I haven't managed to find anything yet but the problem has got worse over the last 2 weeks. The car will not rev above 2900 RPM at all and lacks power all of the time.
I took the car back to my usual Peugeot garage today (2/7/05) for them to have a look at it (for the 3rd time!) and they declared that there is a problem with the turbo boost, but then said I need to rebook the car in as they need another look at it to make sure.
What I cannot understand is that, prior to 2 weeks ago, this was an intermittent problem. Can a turbo have an intermittant boost issue? It wasn't as if was a gradual reduction in power, which I would have expected given the diagnosis. When it was working properly the car had full performance and when it wasn't, it was lack of power and a 2900RPM limit, as if a switch had been flicked.
And why would a boost problem cause the revs to be restricted? I don't know whether the garage are just trying to fob me off because they don't really know what's wrong.
Any ideas?

PowerLee · Post by **PowerLee** » 02 Jul 2005, 21:35

Hi
When the engine control unit detects a fault on the HDI it throws the car in to whats called limited operating strategy or in english, Limp home mode.
While the ECU has the car in limp home mode the fuel pumps output pressure is set at a constant output & the revs will not go above the 2900 limit you have.
Im also surprised the Peugeot garage is taking so long to fix this problem.

wheeler · Post by **wheeler** » 04 Jul 2005, 01:09

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Pugsulike

Can a turbo have an intermittant boost issue?
<hr height="1" noshade id="quote"></blockquote id="quote">
it may not be the turbo itself,it could be the electrical control of the boost or the vaccum side of things.

stubbsy · Post by **stubbsy** » 04 Jul 2005, 05:43

surely the fault code is stored in the ecu even if it is an intermitent fault is it not,and the dealer should be able to retrieve this??????

PowerLee · Post by **PowerLee** » 05 Jul 2005, 00:06

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by stubbsy

surely the fault code is stored in the ecu even if it is an intermitent fault is it not,and the dealer should be able to retrieve this??????
<hr height="1" noshade id="quote"></blockquote id="quote">
I dont know about the HDI, But some ECU systems erase the fault code from the memory if around 20 successful engine cycles are completed.

will16v · Post by **will16v** » 05 Jul 2005, 01:40

Could this be the air flow meter?
Don't know if i'm being thick - but i'm sure a friend had exactly the same problem on a vectra 2.0l TD...