406oc.co.uk

Right, my 406td has been absolutely brilliant in the reliability stakes since i got hold of it in october, it's needed a set of filters and some new glowplugs, but these are just normal consumables.

A few days ago i stopped in at a friends for all of 5 minutes, when i started the car up to leave, the engine management light came on (this things doesn't even have a proper ecu!) and the engine was running like a sack of poop. Missing, jumping, generally being a tart.

Lots of smoke when the engine is running and there is no power at all. Normally i can pull away from the workshops and spin the tyres all the way up the hill (relatively steep hill, the spinning due to my cheap sh*t tyres, not the uber power) whereas now i struggle to get up the hill at all. When i put my foot down the engine is slow to build revs, there's no surge as the turbo comes in, but it will still rev all the way up to 4,500.

I've pulled the injectors and they all have a good spray pattern, i've changed the fuel filter and chucked a dose of cleaner through the system but nothing has changed. Under load the engine is very slugish (almost like an NA), but without load i can hear the turbo spool up.

I thinking it's either the pump playing up (BUT occasionall when i reving at the pump the tickover suddenly goes back to normal, although it doesn't last long), the turbo is giving up (possibly leaking oil into the inlet track causing the engine to burn it) or the particle filter is blocked (which is my biggest doubt as that wouldn't cause the heavy smoke.)

Did a quick vid of the engine jumping/missing/smoking so folks understand what i'm blathering on about.

http://www.youtube.com/watch?v=9fzvC9GwQeU

Quite depressing as this engine is what i cut my teeth on working in a taxi garage and this is the first time i've been stumped by one (and it's my own car!)

Anybody had something similar?

I liked the "help" bit at the end!

Anyway... not sure what could be wrong, but sounds like fuel starvation ... or problem with air supply. Could be a split intercooler hose...

Go along with cj on this ,i would check all the pipes for splits first

This morning it started 2rd try, and it shat out a HUGE cloud of black smoke. Got it down to the workshop and pulled some pipes off, there's oil all down the back of the radiator where the turbo has been breathing oil through the intercooler and into the engine, leaving it to stand overnight has let a nice big puddle of oil settle in the inlet which got blown into the engine when i reved it and the turbo span up.

Intercooler took a pint of petrol to clean, pipes are scabby inside and the shite in the inlet could be used to waterproof your roof.

Left it down the workshop today, can't get it fixed yet (lack of time) but at least i know what the problem is. Might even stick a cone filter on the inlet and bypass the turbo to stop the sh*t getting blown into the motor.


Just need to take off EVERYTHING to get the inlet and turbo off

Well i've got some bits on the way for next week, so it'll be next weekend before i have the time to strip down the engine and replace the turbo & inlet, check if the egr is jammed open (won't be overly upset if i manage to refit everything and forget the egr system), etc. So i'm going to swap in my spare non-turbo lump for the time being so i can get back on the road, really looking forwards to the performance of a 406 estate with nearly 70 bhp

And just to be a sod of a day, the backbox snapped off at the back of the flange, so that'll need sorting too

Hmm, think it's a good guess that the turbo has been breathing more than just air, combination of crappy EGR and the turbo letting go means this snot is inside the head aswell...



I know the inlet is supposed to be slightly texture, but this is taking things too far.


And here it is against the inlet that i'll be replacing it with, from a Xantia without the EGR system


Should have some goodies here tomorrow and i should be back on the road by wednesday

(even in this condition it's a better drive than the wifes corsa ;))

Holly coke!!!

Oh my gawd!

Replacement turbo arrived today, scrapped the clag out of the inlets in the head and washed most of the rest out with a petrol soaked rag.

EGRless turbo and EGRless inlet fitted, engine ran up and STILL smoked. Rolled it out of the workshop and left it running at 2k revs for half an hour (cables ties on the fuel pump makes for a great cruise control ) and the smoke slowly cleared.

Took it for a test drive and it was still missing the extra umph when the turbo spins up, wouldn't rev above 3k (but goes up to 4.5k when reving it at the pump), really struggled on hills.

Decided to sort the busted rear exhaust box and drive the car for a couple of days to see if anything cleared. Couldn't find anything to fit the gap, so we welded in a length of straight pipe
Squirted some carb cleaner into the boost takeoff pipe (the one to the top of the pump) in case some of the snot had jammed the narrow pipe and was causing the underfueling (if the pump doesn't know the engine is boosting, it won't send the extra fuel)

Started it and it STILL smoked a bit. Home time and after about a mile something must have cleared, the engine light went out and BOOM the boost came back and due to the nil back pressure the engine spins up rediculously fast (meaning it will eat what is left of my clutch rather quickly )

But i'm mobile again and loving the increased spin up, it's somewhat grin inducing.

Cool! at least it's running well again but what caused all the cack?

Combination of turbo dumping oil into the airflo and a shitty EGR valve (possibly jammed open due to the oil?) meaning the usual soot was mixing with the oil forminga nice thick sludge.

Looks to me like the thing to do is disable the EGR BEFORE it plays up.
Mine's got a sodding water-cooled heat exchanger betwixt zorst & inlet

(Ready for the environmental backlash should it materialise: He that emitteth not particulates, let him praise the EGR valve)