loss of power/acceleration

[chris dury]

Hi guys,

I'm after a bit of help with my octavia 1.9 tdi. Everything seems fine most of the time but more regulary now when accelerating, I think its only when revs are increasing to around the 3000 mark it seems to loose power. So basically it seems like the turbo just stops working and from then on there is no acceleration from any speed/revs and the car is really slow. Then the next time I drive it it seems to be ok. Like I said though this seems to be happening more often now.

Does anyone know a common simple little issue this could be or am I looking at a new turbo? I remember seeing in the history that the turbo has been changed so hoping that its ok

Thanks for any help

[Oet]

boost pipe issue i think, check the pipework,

you need to get the car scanned for fault codes before thinking you need a new turbo

[chris dury]

Hi Oet,

I'll have a look, which pipework though? Basically just anything into the turbo?

[Phil-E]

That sounds more like the MAF to me. That's the usual symptom that you loose power from 3000rpm onwards.

I had some similar issues recently and managed to cure them by removing the MAF and cleaning with some electrical contact cleaner.

Phil

[chris dury]

cheers Phil,

I'll look at that after checking for obvious hose/pipe leaks. Someone said to me today that the mass air flow valve could be the problem so thats 2 votes for that

[pauldazzle]

Could be the MAF, could be sticking turbo vanes, or a bunch of other things. You really need to get diagnostics on it otherwise you are in danger of throwing parts at the fault hoping to solve the problem. Much better to pin the fault down first.

[Oet]

yup as paul said, get it scanned, will give more info, pysical check of all pipes, disconnect maf see if that does anything

[pauldazzle]

Yeah I forgot with Skoda's & VW TDI's you can disconnect the MAF, & if the car runs better without it you know the MAF is goosed. Cant do that trick on Audi TDI's they just go straight into limp with the MAF unplugged.

[Oet]

didnt know that about the audi tdis!

[pauldazzle]

Yeah, Audi do seem to go thier own way with a lot of stuff. Probably why they're so expensive compared too the rest of VAG.

[pauldazzle]

Oddly the unplugging the MAF trick works on the Audi 1.8T's.

[chris dury]

hi guys,

finally had the computer scanned and no fault codes came up!! Everytime I get this loss of power the car I assume goes into some sort of limp mode as it is extremely slow accelerating for the rest of the journey until you turn the engine off, then its back to normal. I thought as this happens there would be a fault code but apparently not. So I suppose its unplugging the MAF then and seeing what happens. So, Where is the MAF and what does it look like??

[Chris Coates]

Quick one...

When you're accelerating - does it feel like all your power comes along in one big lump?

If so, read either MAF or N75.

I replaced my N75 last month and it was like a world of difference!

Darkside sell a new one that has been working great in mine since. Nice smooth acceleration all the way through the range.

However... It did highlight that my ALH in stock form just wasn't fast enough (I was relying on the overboost condition it kept giving me hahaha!) so started playing with improving power

[Lofty79]

C'mon guys its so obviously sticky vanes, this isnt the first rodeo.

Follow this guide mate, your car is overboosting due to actuator rod unable to move. No new turbo needed

http://www.briskoda....guide-of-sorts/

Edited 28 November, 2012 by Lofty79

[Chris Coates]

This is true - it could most definitely be sticky vanes!

[chris dury]

No Chris, it accelerates fine most of the time, only happens when I accelerate hard around 3000rpm. Then it just looses power an goes into limp mode.

Cheers Lofty, I'll unplug the MAF and give it a go an if its no different then I'll give your oven cleaning procedure a go.

Only thing is, what does the MAF look like and where is it?

[Lofty79]

Its not the maf mate, seen this over a hundred times, its sticky vanes.

The maf is next to the air filter box and has a plug on it, but unplugging this wont reveal anything as on these engines when the maf is unplugged the turbo doesnt run anyway.

So the very fact that it runs well until pushed to 3-3500 revs is definitely sticky vanes, and you need to follow the thread to the letter. Also that it resets once restarted is another give away. I bet also if you are in 5th at 70mph lets say and you floor it itll go into limp aswell.

Very very common problem that most people end up spending £3-600 on getting a new turbo when all it needs is this.

Expect the car to obviously not limp anymore, but also give it alot more oomph aswell, restoring lost power, as in the months leading to sticky vanes the car loses power gradually

Edited 29 November, 2012 by Lofty79

[Lee28]

This may not be due solely to sticky vanes. The N75 a definate probability. My turbo was taken off, cleaned to pristine condition. The fault remained. N75 was the culprit.

Chris C. Is there any difference in the Darkside N75 as opposed to others at half the price? Thanks

[Lofty79]

id bet on it buddy

[Chris Coates]

This may not be due solely to sticky vanes. The N75 a definate probability. My turbo was taken off, cleaned to pristine condition. The fault remained. N75 was the culprit.

Chris C. Is there any difference in the Darkside N75 as opposed to others at half the price? Thanks

Nah, not much difference apart from they're OEM spec - so obviously buying one new from there beats buying a cheapy duplicate.

[Lee28]

Thanks for the info Chris