406oc.co.uk

Hi,just joined yesterday as this seems to be the only place for decent advice on the 406,hope someone can advise.My sri turbo is lacking power seems to me that the turbo is not kicking in,engine noise when accelerating sounds deeper,checked exhaust its ok and have looked at other turbo posts and am going to try and work out what pipe to disconnect so that I can check the turbo is not seized.if the turbo is gone will it harm the engine if not fixed pronto?

if you do have turbo failure, it may contaminate your inlet manifold with oil, but usually, the exhaust gets full of oil and you get a dense blue smoke, on hard accleration, the sri turbo was never that fast, and wasnt always a turbo, there was a crap sri 16v, are you sure your car is a turbo
you should hear the turbo spool/whistle at about 2,000 rpm in 1 st gear when acclerating hard from low revs

jameslxdt wrote:if you do have turbo failure, it may contaminate your inlet manifold with oil, but usually, the exhaust gets full of oil and you get a dense blue smoke, on hard accleration, the sri turbo was never that fast, and wasnt always a turbo, there was a crap sri 16v, are you sure your car is a turbo
you should hear the turbo spool/whistle at about 2,000 rpm in 1 st gear when acclerating hard from low revs

Hi,thanks for the reply, car is a turbo,no smoke of any kind blue,white or black that I can see when accelerating,usually hear the turbo winding down when engine is switched off heard it once yesterday then nothing the next time,car has been sluggish since saturday.

im not 100% sure, you will have to wait for niz406 as he's the turbo god, but more often than not, its not turbo failure but the turbo control valve, i have no idea where it is but i know its cheap

Thanks for your help anyway,will take your advice and wait for the turbo god to try and shed some light,and I will try and check the turbo meanwhile

You should'nt be able to hear the turbo 'winding down' on any car.

Sounds to me that the turbo has got an 'open circuit' because of a large leak somewhere, a hose or the intercooler. Trouble is, the turbo is so hard to inspect on the 406

As James said, Niz has fiddled with his Turbo more times than I've had Hot Dinners............

Fiddle, Fiddle..... hummm that sounds very obscure!

James is on the nail with the actuator control valve. However, if you do not get the management light showing then its not this, more like a boost leak from one of your pipes or a buggered actuator. Check to see if the retaining clip for the actuator rod has disappeared and if it has fit a new one.

No boost is either wastegate open, boost leak or in worse case senario siezed turbo, leaks come from broken stock recirc-valve (black plastic bosch unit), split intercooler tube or plastic endcap.. etc.. When the turbo siezes you will eventually pop the oil seals and blue smoke will become apparent.

A visual way to check without touching any pipes is to watch the charge pipe from the alloy pipe to the intercooler intake, if the pipe collapses when you rev the engine you know the engine is sucking in the charge and the turbo isn't forcing the charge in to the cylinders. Use the throttle linkage under the bonnet to rev the engine whilst watching the pipe or have an assistant rev the engine for you.

Oil in the charge pipes is typical of a worn breather filter, big black disc mounted on cam cover, however some times you will get a little oil in the pipes from the turbo because of wear... nothing major unless you are losing a litre a week!

If ever in doubt always get under the car and pop the black plastic inlet hose off and try spinning the compressor wheel with your fingers.... when the engine is cold of course don't go burning your hands. You may want to also try removing the upper mounting bolts that connect the pipe to the alloy charge pipe makes removal a doddle!

Let us know how you get on,

Any News for us?

niz406 wrote:Any News for us?

Thanks for the reply Niz,not the weather up here for lying under a car too long,
have checked the pipe ,doesnt seem to be collapsing,jacked it up and sounds if
the exhaust is blowing at the front which I didnt pick-up on earlier, going to take
it on monday to my trusty mechanic and put it up on the ramp and check it out better,
hopefully Iam way off with the turbo fault will update you once we have checked
it out cheers for all the help .fingers crossed

Back on BOOST, checked it out today clip for the actuator rod was missing so the wastegate
was constantly open also needed new gasket and fitting kit for the front pipe connection onto the manifold,£50 all-in,thanks for all the replies guys

Oh Yeah..... who's your daddy LMAO

Another happy customer

jameslxdt wrote:if you do have turbo failure, it may contaminate your inlet manifold with oil, but usually, the exhaust gets full of oil and you get a dense blue smoke, on hard accleration, the sri turbo was never that fast, and wasnt always a turbo, there was a crap sri 16v, are you sure your car is a turbo
you should hear the turbo spool/whistle at about 2,000 rpm in 1 st gear when acclerating hard from low revs

I think i have this problem with my turbo.

I've got a small amount of oil on the piston tops and get the smoke on hard accleration.

The back of the car is also covered in black sort.

Whats the causing it and is it easy/cheap to fix

if the car still pulls and feels like the turbo is boosting then most likely the oil seals have failed, the turbo will have a low oil pressure and eventually it will seize up, you can buy a turbo overhaull kit of ebay quite cheap, this will save you quite a bit of money as a recon/new turbo is very expensive, are you sure it only smokes when its on boost

It smokes a little on idle to.

Cars not used much so i will sort the turbo out.

Thanks for the help