hey all. been awhile. i went to pick up my i30 from the smash repairs today. after the misses gave it a little nudge. and as i drove i off i immediately noticed a significant lack of power. the turbo wasn't boosting at all. i spun back around and took it back.
i checked over all the piping and everything seems fine. it hasnt got any engine lights on at all and it doesn't smoke when driving.
to me it seems like an electrical issue with the vgt or something,
has anyone else had issues like this after an accident. we never drove it after the accident. until now.

[Dazzler]

 

Did the nudge cause any mechanical damage that you know of or just cosmetic? Does the engine sound "normal"?

Hopefully only a wire they forgot to connect or something... You could try disconnecting battery for at least 30 minutes to reset the ECU. 

only ac condenser, intercooler and radiator. engine idles and revs as normal just with no power. not even a boost leak sound

[Dazzler]

only ac condenser, intercooler and radiator. engine idles and revs as normal just with no power. not even a boost leak sound

The intercooler is obviously connected to the turbo, so I would handball the problem back to the repairer... 

yeah its in there now. im not picking it up till they fix it. i was just trying to work out with was wrong.

turned out to be a "ets switch" he called it. got broken by the radiator hose. so its on order and we have to wait till monday now for the car

[Dazzler]

Hopefully that fixes it

[ibrokeit]

Cool they seemed to find the fault 

I suspect ETS might be 'Electronic Temperature Switch' - which probably makes sense.

[Doggie 1]

Ah, so it's not an Extra Terrestrial's Scrotum then......

[ibrokeit]

I was going by 'broken by the radiator pipe' and that radiator, intercooler, etc. had been fixed/replaced - some form of temperature switch would make sense... possibly the turbo not being used because ECU couldn't determine if intercooler was cooling enough.

However that was just a big fat guess - could very well be as you say (member 5716 not found)... though I was sought of under the impression that some turbos basically run all the time (depending on design).

Doggie 1 probably not, do you get those out your way? 

i think being a vgt turbo they can basically "shut them off" by adjusting the vains in them so the exhaust just passes through. and temperature sensor makes the most sense. but ill find out when i pick up the car on monday.

[ibrokeit]

i think being a vgt turbo they can basically "shut them off" by adjusting the vains in them so the exhaust just passes through. and temperature sensor makes the most sense. but ill find out when i pick up the car on monday.

Thank you - I just went and learned something new! Yup - you're right!  Had to go look up about vgt turbos (haven't had much experience with turbos, knew the basics of operation... use exhaust gas to compress cool intake gas/air, divert/dump exhaust gases pre-turbo to control/turn-off).

------

From my quick study... the vanes control the 'angle of attack' (for want of better term) of the gases onto the turbine (exhaust impeller) and also the area the gases can flow thru - which appears to be called the 'aspect ratio' this dictates the speed of the turbo shaft and so the compression of inflow gases via. the compressor (inflow impeller).

With the vanes fully open there basically is no AoA and wide area - so the turbo shaft rotates at whatever speed the pressure of gases being directed by the fixed geometry vanes of the turbine dictates - I assume that, at low-revs, this would give negligible compression by the compressor (compressor inflow vs outflow - to engine - pressure).   As they close they a) restrict airflow (area) - increasing the pressure/velocity of gases flowing thru the turbine; and b) AoA (meaning more energy transferred due to that); thereby increasing the shaft speed thereby compression produced by compressor on inflow gases.   At higher-revs the vanes could be opened with their effect on gas velocity not required due to the exhaust gases being at higher velocities.

Of course, as with any fluid flow, if the flow is restricted too much... power is lost so shaft speed (therefor intake compression) decreases; and if vanes are fully closed (if they can be) the shaft would only be rotated by the pressure of the inflow gases being sucked/dragged over the intake impeller by the engine - which would likely have a negative effect on power of engine.   This assumes some form of pressure bypass for exhaust gases not passing to the turbine (due to closed vanes) - as without it would probably have a very negative effect on engine power.   I assume, for automotive applications at least, there is probably a physical 'stop' (or the design) prevents full closure.

[ibrokeit]

If anyone is interested this seems to be a nice animation - turbine side orange; compressor side blue:    VTG Turbocharger Animation - YouTube

The above was the second animation I came across.

The first (done by someone else) had the vanes pointing in the opposite direction to the turbine intake flow (as indicated by turbine (fixed) vanes and turbine rotation; and also the normal turbine setup of inflow on edge, outflow via center)... i.e. the gases would have had to make a near 180 degree turn around the vanes to turn the turbine     worryingly it seems to be produced by a company that does training videos - marketing them to schools, etc..   I ignored the fact the center point (indicated by a peak) of the animated turbine was off-center from the center of rotation - which I suspect would be very bad on a real turbo!

that pretty well sums it up. they went into alot more detail during my apprenticeship but in the real world unless you specialise in turbos you unbolt it and bolt on a new one and send the old one in to get some money back lol.

the main reason for them is to allow a turbo that is too big to work at low revs to work at low revs. which gives good high end power as well as low end power, as it can also act as a small turbo when needed.

and all that so the engines can pass the ever increasing emission laws.

[ibrokeit]

that pretty well sums it up. they went into alot more detail during my apprenticeship but in the real world unless you specialise in turbos you unbolt it and bolt on a new one and send the old one in to get some money back lol.

Sound like some of the AC stuff I did for my tertiary qualification (electrotech) - was all very interesting, good to know, but unless you working in a specific area you never use it (and probably forget the finer points). And it is more cost-effective to replace and sell/send old for refurbishment.

the main reason for them is to allow a turbo that is too big to work at low revs to work at low revs. which gives good high end power as well as low end power, as it can also act as a small turbo when needed.

and all that so the engines can pass the ever increasing emission laws.

Uh huh - but it can be said that is better for the environment.

Uh huh - but it can be said that is better for the environment.

it could be worse, it could be a VW.

[ibrokeit]

 

[shungers]

Hey, did they end up sorting this out? I have a similar problem with lack of power which I think is related to the turbo not kicking in properly.

[ibrokeit]

Hopefully the Author is still reading the forum and/or following the thread (via. notifications).  As you don't need to be logged in for some aspects, though they haven't logged in since the end of Sept.

[Lakes]

Could have been anything , but doubt a panel beater could work out the problem.
When the vgt type turbo's loose low end grunt. It would normally be the vacume hose that controls most Vgt , when that hose gets a hole in it or is disconnected, the variable pitch blades stop moving so you don't get same low end or low rev boost. A friend had that happen with a diesel sprinter van, he thought motor was stuffed but. Someone fixed it & it was performing like new.
Another problem with that type turbo, is if you drive slow all the time never giving it the stick once a week or in a while. The variable pitch blades become carboned up in the slots that limit there movement. So in other words they can jam up.
We had a member when the club was first formed that disconnected the vacume hose then put a plug to seal & stop vacume leak. He only did that testing to see if he could increase economy. Well he claimed it increased economy , think he got down in the 3L/ 100K . But he said the motor lost a lot of low end torque.
Just mentioning this to try to explain. How the VGT works.
If you go to Garett turbo com think they have a moving diagram of this type hair dryer .

[Phil №❶]

I thought that on switch off, the turbo vanes were automatically put through full range movement to stop any carbon build up. 

[shungers]

FYI, problem is now fixed.  I had no low end torque so did some checks.
- The vacuum pump was working but vanes weren't moving for some reason.
- Played with the VGT vacuum bell and actuated the vanes a few times.
- Disconnected the vacuum line and blew it out.
- Reconnected and it started working again but intermittently so thought it was the vacuum pump playing up...
- Waited a day and it started working more consistently.
- Now working 100% of the time for the last 2.5 weeks.

Hope this helps.

[ibrokeit]

Thanks for the report back.

Sounds interesting that it got better over time... wonder what is happening there.

[Dazzler]

FYI, problem is now fixed.  I had no low end torque so did some checks.
- The vacuum pump was working but vanes weren't moving for some reason.
- Played with the VGT vacuum bell and actuated the vanes a few times.
- Disconnected the vacuum line and blew it out.
- Reconnected and it started working again but intermittently so thought it was the vacuum pump playing up...
- Waited a day and it started working more consistently.
- Now working 100% of the time for the last 2.5 weeks.

Hope this helps.

Could you have stopped suddenly after a bit of hard driving? Oil may have burnt on to the vanes. Might be an idea to let the engine idle for maybe 30 seconds to  a minute if in that situation. Not accusing you, just an observation. 

They sorted mine out. It was the vacuum for the turbo. It got broken in the accident.

But now it's got something new the AC is starting to play up. Takes ages to get cold. Sometimes. Only started it since the accident.

[Phil №❶]

Possible small gas leak. Needs UV light inspection, IMO.

yeah i got i uv torch just waiting on a battery for it. apparently the pressures are all good.

[ibrokeit]

yeah i got i uv torch just waiting on a battery for it. apparently the pressures are all good.

Possibly something for a new topic - however...

If the pressure is all good, and there is no leaks, then maybe (and I might be right off base here) electric clutch for the A/C pully isn't working/bad-connection/etc. (damaged/movement in collision?)... that is if it uses such (I seem to recall it does - but not why I 'know').