HDi 90 rough & poor economy - Dzl
Hi all.

My 406 HDi 90 (02, 90k) has recently developed the following symptoms. I will take the car back to the dealer as it is still under warranty, but they are particularly useless (still trying to fix the satnav cd drive) so I'd like some suggestions about what the problem could be.

(i) A rattling noise. I used to have a box of drinking glasses in the boot, and it sounds like those rattling. It is particularly noticeable after a cold start, and can usually be produced by holding the engine speed at about 1500rpm.

(ii) Holding the engine speed at 1500rpm, the needle wobbles noticably.

(iii) The engine sounds louder and "growls" more.

(iv) Loss of torque at very low rpm. It used to be happy down to 1100 but now "chugs" from about 1300.

(v) Poor economy. I always measure brim-to-brim and find that the computer is consistently under-reads by 8mpg (the dealer could not fix this shocking inaccuracy either). The last fill indicated -3mpg from normal, the computer now reads -6mpg from normal.

Thanks.
HDi 90 rough & poor economy - Bromptonaut
See car by car breakdown re trouble with damped cambelt pulleys on these engines. Symptom (i) is particularly indicative of trouble in this area.

So get the cam belt and its associated pulleys checked now. Avoid driving the car in the meantime
HDi 90 rough & poor economy - Dzl
I took it to Peugeot and explained the symptoms. They said that no faults were recorded in the ecu and therefore nothing was wrong. Unsatisfied, I demonstrated the noise to the mechanic who said it was "probably diesel knock", and that the fall in efficiency "could be due to anything". He also said that I had been misinformed about cambelt pulleys needing replacing, and that this was not necessary and never done. They charged me £47.

The car is now less efficient than my old 406 XUD was!

I will take the car to a local independent garage I have used before and ask them to check the pulleys and timing. If they find a problem then I feel that Peugeot ought to refund me, how should I approach this?

Thanks.
HDi 90 rough & poor economy - David Horn
I would simply get it in writing from the dealer that they will pay any costs for repair should the cambelt fail prior to the normal replacement interval due to a faulty pulley.

If they're unwilling to do that then they know something you don't. May also be worth taking in a copy of the CBCB for your car and show them.
HDi 90 rough & poor economy - RichardW
It's enough to make you bang your head on a brick wall isn't it? "Computer says it's OK, guv, nothing we can do"...so what about the oil trail it's leaving behind? "Computer...." etc

There is definitely an issue with HDi crankshaft pulleys coming adrift. The low rpm noises (especially at start up) are exactly the right symptoms. However, I would be worried about the lack of power, rough running and poor economy. This is suggesting that the cambelt has already jumped a tooth or two. As mention above get it direct to your local independant - avoid driving it! If he says pulleys are not a problem, find another garage that says, "yeah, done loads of those".

Here's a link to a thread by DL (who fixes them for a living) of just this type of failure - over 2 years ago!

www.honestjohn.co.uk/forum/post/index.htm?t=15983&...e
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RichardW

Is it illogical? It must be Citroen....
HDi 90 rough & poor economy - Bromptonaut
Ignorance/arrogance of main dealers never ceases to amaze.

Above similar to my experience with HDi Xantia. Booked it in for cambelt change and said I'd read about trouble with pulleys and could the sort it at same time. Was told they knew nothing about this issue, that pulley looked OK and was best left alone.

Six months later a few noises like Dzl mentions followed by (fortunatley low speed and low damage) failure. Still a big bill though although dealer had good grace to meet most of it
HDi 90 rough & poor economy - dieselhead
Got a bill last week for over £1000 from peugeot main dealer to rectify intermittent non starting on a 2000 306 hdi.
They replaced " the air flow valve" one fuel injector, crank pulley and when we picked it up it still wouldn't start!.
Left the car at garage for another week and they replaced high pressure fuel pump and fuel rail for another £450. It now runs fine but can't help thinking they just expensively replaced parts hoping it would cure the fault.

HDi 90 rough & poor economy - Dzl
The theory is a faulty throttle position sensor. Although this is a clear improvement on Peugeot's diagnosis, I don't understand how this explains my symptoms. Answers on an internet forum please...
HDi 90 rough & poor economy - Screwloose
Dzl

The accelerator pedal position sensor code is a regularly seen one. There is a wiring mod to try and stop it recurring; if you got a fault-code of P0120/0220 then this can help. If you got P0121/0221 then it rarely does.

The noise, loss of power and wobbly tacho would suggest a disintegrating "dual-mass" flywheel.
HDi 90 rough & poor economy - DL
Screwloose - would you mind enlightening me on the wiring mod for the demand sensor? I see these faults on a weekly basis....
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groups.msn.com/honestjohn - Pictures say a thousand words.....
HDi 90 rough & poor economy - Screwloose
Dzl

What's the engine code on yours? On an RHY it's essentially an extra earth for the MAF.
HDi 90 rough & poor economy - Dzl
Hi all, thanks for your suggestions.

(Engine code is 8BRHY.)

The garage have removed and replaced the throttle position potentiometer. They said that it was indeed faulty, having a "weak spot".

I went for a drive with the mechanic who agrees that the car is slow and rattles. Of course the throttle potentiometer had no effect on this. I quizzed the mechanic about what he thought the problem could be. He suggested an EGR problem, MAF sensor, or turbo leak. I mentioned the cambelt as I had an XUD 406 on which it slipped, but this was dismissed.
The EGR will be investigated next Wednesday.

I like the EGR theory because the car is noisiest when cold and shockingly inefficient under heavy load, i.e., when the valve is supposed to be closed. The valve is supposed to be open when cruising, and I can still get 50mpg at 75mph on the motorway although it runs out of puff below 2700rpm, up from 2500rpm. (Its now more efficient to drive it at 75 than 70.)

More Questions:

The warranty company say they will not pay for "diagnostic work", so I had to pay £35 for the garage to diagnose the throttle potentiometer. (And of course £47 for Peugeot to do nothing.) Is this normal? I shall approach Peugeot once the problem has been fully solved.

The brake pad wear warning light is coming on, but brake pads are not covered under warranty. As the car has done only 3000 miles in under 3 months, I feel that I should not have to pay for this. Am I wrong?

Ta.
Dzl.
HDi 90 rough & poor economy - boab67
Got a bill last week for over £1000 from peugeot main
dealer to rectify intermittent non starting on a 2000 306
hdi.
They replaced " the air flow valve" one fuel
injector, crank pulley and when we picked it up it still
wouldn't start!.
Left the car at garage for another week and they
replaced high pressure fuel pump and fuel rail for another £450.
It now runs fine but can't help thinking they just
expensively replaced parts hoping it would cure the fault.


Dieselhead if this were to happen again i suggest you remove the camshaft sensor,give it a clean then re-fit it.I had bother before with a 306hdi non-starting and tried this just out of curiosity and hey-presto,engine fired up and an expensive trip to a peugeot dealer aborted.
HDi 90 rough & poor economy - Mike M
Dzl, When my brake pad wear warning light came on on my 406 about 1000 miles after changing the brake pads, it was because the wear sensing leads attached to the pads had been incorrectly routed. The insulation on the leads had been worn away by contact with the brake disk and were shorting out to ground, thus causing the light to come on. Some insulation tape and proper routing solved the problem.

Mike
HDi 90 rough & poor economy - helicopter
I would check out your catalytic converter - glass rattling tinkling noises sounds to me like the innards have shattered and blocked the exhaust.

The resultant back pressure could be causing the sluggishness,

You say the engine is noisier and this also could be caused by cat failure.