[Deanpompey]

Ok so when i got my van it was running 18psi boost due to a duff n75. ran like this for about 8weeks with no problems except ecu putting her into limp above 3k in 5th.

Then i got round to replacing the n75, and she ran at about 12psi for about 4weeks, again with no problems whatsoever.

I had my van remapped on friday by a well known company ( i wont name names until this is all cleared up) started off at 122.3 bhp, came out at 149.7bhp. boost was at 12-14psi. One thing to note is that the wastegate actuator had to be adjusted to hold boost, but yet it never had a problem holding boost when it was at 18psi...?

Van didnt really feel much different except in 3rd slightly pokier, and 5th where the extra torque was immediately apparent. could go from 50mph to 80mph without breaking a sweat, even uphill. did notice a lot more smoke in the rear view, but put this down to extra fuelling( couldnt tell colour as it was past dark by then).

so did a fair old drive home and let turbo cool down before switching van off.

Went out following morning and started her up and she was lethargic and missfiring. let her run for about 20-30secs before prodding the throttle wherby she blew out blue and black smoke in equal amounts and misfired like crazy. Drove van to end of my road and back (short road) and parked her up having noted no boost ( guage was actually sucking into vacuum instead of boost pressure) and no turbo whistle.

Removed i/c and pipework to discover the pipes and turbo were FULL of oil.

So the turbo has died.

i really really dont see why the turbo would just suddenly die when the boost levels were LESS than it was running previously with no issues. and i also cant understand why the actuator needed adjusting to hold less boost than it was previously managing to hold with no problem at all?
I have had no warnings of a turbo on the way out, no blue smoke or oil consumption, no change in noise, nothing, so i am really struggling to figure this one out!

If anyone can shed any light on this, or has any ideas/theories/similar experiences that would be great because to say i am a bit miffed is putting it lightly!

I will not be getting lairy with the company involved, whats happened has happened and thats that, but i would really like a reason not to be able to blame them for this, because whichever way i look at it it was fine before the map, even running far higher boost pressure, and yet one journey after the map and its dead. its a bit of a big coincedence :*

 

[JonT4]

I believe in coincidence but it can't always be blamed so be open minded until you get to the bottom of this.

Firstly had you checked the oil level recently before it went pop?

Ok now the more likely causes....

What do you mean "to hold boost"? Was boost dropping off at high revs? If so, that's a sign of running out of fuel. This should all be done in the map without needing to manually alter the actuator. Adjusting the actuator is (normally) a crude way of increasing boost without mapping. You shouldn't be able to see plumes of smoke behind you but you should have a puff of black when you plant your foot and a steady yet light haze from the exhaust throughout the rev range. The more power you aim for the higher the smoke output, unfortunately people worry more about gaining pub talk figures than a strong *healthy, reliable* engine. Was 14psi constant or did the engine peak first?

 

[Deanpompey]

I had checked the oil the day before the map prior to my journey and it was spot on, just a touch below max level.

And yes i was told the boost wasnt holding at 14psi hence adjusting the actuator to compensate.

when it was on the rolling road it was just a puff of black smoke when first hitting the pedal and coming on boost, however on the way home there seemed to be an awful lot of smoke, a constant haze behind me when accelerating. i wasnt sure whether this was just smoke i couldnt see in daylight being magnified by cars headlights, but in hindsight i dont think it was just that

The boost peaked at about 14/15psi, then backed down to about 12/13psi.

I wasnt aiming for big figures either, i never asked for a specific power level, just wanted a slightly quicker, more economical van....
and on that note it actually seemed worse on fuel on the return trip, couldnt really be 100% on that as it was second half of tank, but i was driving very steadily on way back at 70/80mph max and was about 30miles down on what i normally get out of tank when i had to fill up.

 

[JonT4]

I had checked the oil the day before the map prior to my journey and it was spot on, just a touch below max level.

And yes i was told the boost wasnt holding at 14psi hence adjusting the actuator to compensate. Poor map.


The boost peaked at about 14/15psi, then backed down to about 12/13psi. Poor map.

Only my opinion and I'm NOT a mechanic but if your fueling is correct you should boost straight to what you set it at it it should hold there until peak revs. Mapping is an art that requires skill and patience anyone can throw more fuel into an engine. My engine jumps instantly to 1.3B and doesn't even twitch until I let off and I can't even map my engine! (That wasn't meant to sound braggy). Maybe something got altered in the map by mistake. I would ask for a copy. The ideal ratio for maximum power is stoichiometric. That is, the one where there are two oxygen molecules present in the air for every carbon in the fuel and one oxygen molecule present for every two hydrogen. This is around 16:1 air:fuel by weight for diesel. That said, the real ideal ratio is a little more lean than stoichiometric because a diesel cannot perfectly mix the fuel and air during combustion so some of the free oxygen always goes to waste, (hence the black smoke). Some of the fuel is not burning completely and making soot.

Anytime you start injecting more fuel than you can burn, you are just wasting the fuel. You will get no more power by exceeding stoichiometric.

 

[Deanpompey]

thanks for the advice. i will be bringing this up with the persons involved when i speak to them.

anybody else have anything to contribute?

 

[anthony1980]

thanks for the advice. i will be bringing this up with the persons involved when i speak to them.

anybody else have anything to contribute?

Turbos only really dye from lack of oil been in the trade for years only tine seen them gone is low oil pressure or no oil at all causes bearings to fail not really had issues with fuel causing issues but if pressure to high yeah strange one there