Do you know your car's MoT and mileage history? Our user profiles will show you for FREE | No thanks
pug 406 turbo diesel problems - prolst263f
Hoping someone can shed some light on my snag

My Pug 406 started losing power on hills a few days ago and the accelaration on the flat was also a bit slow. I have also noticed an increase in black smoke over the last couple of days.

THis came to a head yester day when an alarming knocking sound was heard as the tacho went passed 2,500 revs ( about when the turbo normally kicks in)

running normally the engine sounds okay its only when the revs go above 2,500.

Am I right to suspect the turbo and if so can someone give me a ballpark figure on how much this is likely to set me back?

Appreciate any help or ideas

pug 406 turbo diesel problems - mgk luton beds
sounds like poss turbo prob but might be head gasket prob sound like its running on its own oil black smoke on diesels is either over fueling or oil getting in
poss on turbo diesel if not driven hard will kick out black smog
when reved hard ie first rev on mot smoke test
did car accerate when noise came
pug 406 turbo diesel problems - pienmash
if ya going to keep the car for next couple of years,go to a specialist turbo shop and get a tuned turbo unit as puegeot or any retailer only supply turbos that give you 50 per cent power,they supply these units because there made to puegeot spec,which they down tune to make the car more economical,also if your turbo unit has blown a seal it would produce black smoke
pug 406 turbo diesel problems - autumnboy
It sounds if its overfueling itself.
Have you checked the obvious such as the air filter. Are the hoses between the filter housing and turbo in good order, such as 'no signs of the hoses clasping when the turbo comes in for extra air' or no blockages at the intake to the filter assembly.
Otherwise there maybe a fault on the overfueling device in the injector pump connected with the turbo boost pressure.

Don't think its the turbo, because you are having black smoke from too much fuel (where there seems to be boost pressure to trigger the overfuel device) causing the knock, if was blue then it maybe the turbo seals that have blown using engine oil.

Advise you take it to a local OFFICAL diesel pump repair company, and not to a local or dealer garage or you will charged extra for them to sub-contract it to the diesel pump company.
pug 406 turbo diesel problems - Robin the Technician
Hi Pete,
Before you go tto any expense, first check the intercooler pipe for a split. The pipe runs down the front centre of the engine and curves off to the right (as you look at it). I had identical symptoms with mine a month or two ago and it turned out this pipe was split. The car would tick over without problems but the minute you put your foot down whilst driving it would struggle and lose power. I seem to remember the pipe was about £35 ish, but its worth checking out. If its split it will cause an imbalance to the air entering the engine.

Hope this helps...

These are the views of Robin the Technician with 35 years in the trade. I fix, therefore I am...

Ask Honest John

Value my car

Amount to borrow
Sorry. The minimum loan amount is £1000
To pay back over

My credit score

Best available rate 9.20%

Total repayment £9,304.93

Total cost of credit £1,804.93


60 monthly payments

Apply now

Representative example

The Representative APR is 13.2% (fixed) so if you borrow £7,500 over 4 years at a rate of 13.2% p.a (fixed) you will repay £199.21 per month and repay £9562.20 in total.