How to tell if a turbo has been cleaned

[Ibiza2000]

To cut a long story short, I had mechanic (A) clean my turbo out and u stick it's vnt veins on my Leon tdi, he also had remapped it for me, when I got it back I thought great more lowend power, I can hear the turbo more ferocious than before, thought nothing of it, didn't really wana kick it untill I had my cam belt done as it was at 100k and hadn't had a belt done

So mechanic (B) took the car this morning - as I wanted to get a second opinion anyway, he fitted the new belt, but said the car was flat as hell, he'd drive a few and they were alot more powerful, said it could be either a maf, stuck egr or knackered turbo I'd said the turbo had been removed and cleaned, he'd said 1 u can't clean a turbo as once it's in bits it's no good, and 2 it looks like the turbo hasn't been removed but someone's cleaned the egr

Now Im not gonna pretend to know about turbos and how they work and effect the car, I got my car back and it seemed to kick hell of alot better than before but nOw mechanic B has worried me sayin it's flat, ad the turbo ain't been cleaned, any way to check this as you can understand I'm a bit p'd off and dont wana start buying MAFs and stuff just yet

Please help :/

 

[x24sevenbikerx]

if you disconnect the MAF and go for a drive and it pulls alot better then the maf is faulty

abouyt the turbo weather its been cleaned or whatever , couldnt tell you buddy

 

[x24sevenbikerx]

also you getting any fault codes or anything like that?

 

[Muttley]

Mechanic B is demonstrating profound ignorance.

There is a nice stripdown of a VNT15 turbo here.

Although this is not attached to an engine, it shows how easy the stripdown/clean/reassembly process is. The biggest problem is removing the turbo from the engine, as the nuts and bolts, having been heat-cycled for thousands of miles, will be corroded and difficult to shift.

If the center bearing is undisturbed, then the remainder of the work is within DIY scope.

I suspect the easiest way to examine the turbo will be to take off the exhaust downpipe and look at the turbine wheel. But if it's been used since having been cleaned, there will be some soot on the blades. You'd have to take a guess as to how much had been removed.

Cleaning the turbo, though, is about freeing up the variable geometry vanes, and you can't see them unless you open up the turbo.

If your EGR was stuck you'd be going into limp mode when overtaking at motorway speeds. To test the MAF, disconnect it and go for a drive, if there is no change in the car's performance then the MAF is not working.

 

[alias]

As stated above, the only way to tell short of stripping the turbo down is to check the turbine (exhaust) side or the point where the turbo joins the ex. manifold assuming its not a one piece unit. However, even if cleaned, there's going to be a fair amount of staining even with the coke deposits removed so it'll be hard to tell. The best way to tell if mechanic A is even telling the truth is to see if the nuts/bolts holding the turbo on are new. The old ones should have been done away with if they were taken off.

 

[rsrich]

www.turbocleaner.co.uk
www.cleanmyengine.co.uk

Yes it really does work..

 

[Ibiza2000]

So really I'd have no way of telling :/

Mech b was right about it being 'flat' u can tell the turbo doesn't kick in, I spoke to mech a that did the work he recons a boost pressure sensor,before it had work, it had a vag com reading, it red back positive charge deviation, maf sensor, coolant sensor and injection start timing

I want it done again to see if any of these faults are gone, spose that's next but any idea why my turbo could not be kickin in from the info made known?

 

[Muttley]

I can't understand your post: are you saying that mechanic A told you that your car was showing faults to do with all those items?

If so then he should have cleared the codes after he'd done the work, so that if you see them reappear then there is still a fault. That's the best you can do now, clear the codes, drive for a few days, see which ones reappear.

As for why the turbo is not working: You say mechanic A cleaned the turbo and gave you a remap.

What is the remap supposed to deliver? More power, better economy, faster acceleration low down?

Does he have any credentials as a remapper? Can you talk to anyone else who've had their cars remapped by him? Did he give any guarantee?

The tools to perform remapping are relatively easy to get hold of, but the skill to rewrite a map to produce good results safely is not. Unless this man has solid credentials, I'd be looking at the map as the first dubious factor. Trouble is, if he's an unskilled remapper, asking for him to take the map off isn't necessarily going to help.

If not the map then:-

Vacuum actuator
Vacuum lines
N75 vacuum and electrical connections

- all need checking. It sounds to me as if the turbo isn't being driven by the ECU at all: the default position of the vanes is fully open, which gives minimum boost at low revs.

 

[ibizacupra]

www.turbocleaner.co.uk
www.cleanmyengine.co.uk

Yes it really does work..

i will second that
had a poorly pd130 golf 4 in last week...

tried the revive... and jeez... the crap which came out of it was stunning... Looked like a local fog for a while as it cleaned out all sorts of soot etc.

before car was blue smoking and had limp mode issues from overboost (sticky vnt)

afterwards, no smoke.. and no limp modes 1 week on..

car in question was not a looked after car, and this brought some life back into it again.

 

[Ibiza2000]

Ok muttley, I get what your saying, let me make it a bit more clearer as iv confused myself lol

Mechanic a had cleaned my turbo, suposidly, and remapped me, he cleared the faults with the vag com, he said that the reappearing faults were boost pressure sensor, and coolant temp

I had dubunit give a reading previously, they had a faulty maf sensor, injection start timing and coolant sensor, and positive charge deviation

Mechanic b just did a cambelt, as I don't trust mech a no more after all the problems occurring, mech b done the work and said that the turbo simply had no power,

I had no qualms with the power untill I took it to see what high end was like (as I didn't wana strain an unchanged belt in 100k) and I can clearly tell the turbo just don't kickin, mech a iv spoke to three people since my issues an there all ok, one including a golf with my same engine code, he'd supposedly put on the same map as that, so I think the maps ok, in sure my issue is lying with the turbo again, I haven't had a vag con reading since mech a remapped me, as explained tho mech b suspects ye turbo wasn't touched, raising my suspicions, ino it's confusing but hope that makes it clearer, I don't know what to do from now as I don't wana waste money as iv spent over £400 in three weeks on it and my issues still ain't solved, iv questioned mech a and he said the turbo was cleaned and seemed fine with the questioning, and said let him no what I find, imfinding it hard to find a local vag reader at the minute making my issue twice as worse

 

[cupra.al]

www.turbocleaner.co.uk
www.cleanmyengine.co.uk

Yes it really does work..

i will second that
had a poorly pd130 golf 4 in last week...

tried the revive... and jeez... the crap which came out of it was stunning... Looked like a local fog for a while as it cleaned out all sorts of soot etc.

before car was blue smoking and had limp mode issues from overboost (sticky vnt)

afterwards, no smoke.. and no limp modes 1 week on..

car in question was not a looked after car, and this brought some life back into it again.

might have to try this now ive read bills post.

 

[Muttley]

Ibiza 2000. Very hard to understand you without punctuation. I'm an old man, my sight isn't particularly great, and your post is hard for me to parse.

I'm having trouble understanding this remap. What made you decide to have it done? It's not usually a spur-of-the-moment decision, and I for one would be very loth to have anything but a very reputable company remap my car.

What was promised from the remap? What do you expect it to give you?

What is the base engine? Are we talking about a TDI 90, 110, 130 or 150? Your profile says you drive an Ibiza, so that's no help.


I have a lot of difficulty understanding why anyone expects the turbo to "kick in", as though there will suddenly be a punch in the back. The turbo is delivering charge pressurisation from maybe 1500 rpm, and the VNT turbos give full boost from 2000 or so. There isn't a switch that suddenly brings it into play. So what makes you think that the turbo isn't delivering.

The only sure way to check is on a rolling road, but that isn't free.

Can Mech B explain in a bit more detail why he doesn't think the turbo has been touched?

Can Mech A explain what you should expect from the remap?

Try putting a post in the VAG-com section asking for someone in your area that is willing to come and do some readings for you for a reasonable contribution (beer, petrol money, something like that - many will do it for free).

 

[Ibiza2000]

Sorry apologies English ain't my strong point, I'll try and answer all the questions

As regards to the remap decision, the guy that mapped me has been dealing with maps for around three years, and I wanted a map and asked if he could map me and clean my turbo out, he fitted a reasonably priced deal for me as iv sent a few freinds he's way for different bits of work,

I was promised more low end torque and high bhp, from the map that's what I expected too, it certainly gives better acceleration as my acceleration was like a tank previously, I own a ALH engine, so standard its at 89bhp,

As for turbo expectations, previously my turbo before all my problems occurred threw me Back in my seat at around 2200rpm which admittedly was strange for so much power in a 'baby' spec engine, now I feel nothing close to that no cut in or out points,

Previously it used to hit a flat spot around 1900 rpm, now there are now flat spots from what I can feel but no charge either

Mech b suspects the turbo wasn't cleaned as he says it looks like it hasn't been touched, but he only worked on top end of the engine not underneath, u couldn't tell right? Just from looking at the top end of it?

I'll be sure to update my profile and to also post in the vag com section, can u get a reading from a vag com as in expected ecu values to actual values with that graph block reader?

Thanks for your help, do u need any other info?

 

[Muttley]

Ibiza2000 wrote

Sorry apologies English ain't my strong point, I'll try and answer all the questions​

Thanks, I find this post so much easier to read and can concentrate on answering your questions

As regards to the remap decision, the guy that mapped me has been dealing with maps for around three years, and I wanted a map and asked if he could map me and clean my turbo out, he fitted a reasonably priced deal for me as iv sent a few freinds he's way for different bits of work,​

So you are acting as a guinea pig, or a pioneer, helping him try out his mapping skills on your car? I'd want to be paid to do that, but of course I don't know the guy or your working relationship with him.

I was promised more low end torque and high bhp, from the map that's what I expected too, it certainly gives better acceleration as my acceleration was like a tank previously, I own a ALH engine, so standard its at 89bhp, ​

Excellent information and this helps a great deal.

ALH is the last of the TDI 90 engines, and is different from all the previous ones in that it has a VNT turbo: all the earlier ones had a wastegate turbo. This means there is potentially a lot to be gained from remapping, more than any other TDI 90 as the ALH is more-or-less an ASV with a more restrictive map: however, I believe the ALH also has slightly smaller injectors, another poster (Seatmann, who has a lot of TDI tuning experience) did say that.

Better acceleration could well be an indication of remapping. More top end power is sometimes difficult to discern, as most of us spend very little time at full bore (unless you're on a racetrack or drag strip).

Does it put out more smoke with your foot flat to the floor?

Incidentally, if you had any other TDI 90, cleaning out the turbo would be of almost no benefit as there wouldn't be any vanes to unstick. The wastegate-turbo engines (1Z, AGR, AHU for instance) suffer from a different problem, which is the EGR valve sticking. This allows exhaust pressure into the inlet and as revs rise, the result is overboost and limp mode.

As for turbo expectations, previously my turbo before all my problems occurred threw me Back in my seat at around 2200rpm which admittedly was strange for so much power in a 'baby' spec engine, now I feel nothing close to that no cut in or out points,​

Interesting. I had a TDI 90 Ibiza Mk.2, and never experienced that sort of power delivery, but that was an AHU engine. I suspect, though, that the remap has eliminated that power surge by bringing the torque in earlier, hence your faster acceleration.

Previously it used to hit a flat spot around 1900 rpm, now there are now flat spots from what I can feel but no charge either​

The remap has eliminated the flat spot and smoothed out the power delivery. You've got more power up the rev range, which you should see from comparing 1/4 mile figures or 30-60 acceleration times. Not always easy to spot by "feel", especially if the map has eliminated a flat spot - you've come to expect it,and the power recovery.

Mech b suspects the turbo wasn't cleaned as he says it looks like it hasn't been touched, but he only worked on top end of the engine not underneath, u couldn't tell right? Just from looking at the top end of it?​

You're absolutely right, Mech B is looking for something that isn't there, evidence that the turbo has been removed/disassembled. I would expect Mech A to have used Innotec or something similar, which doesn't require disassembly, just taking off the downpipe or the EGR pipe to get the cleaning solution in to the exhaust turbine.

I'll be sure to update my profile and to also post in the vag com section, can u get a reading from a vag com as in expected ecu values to actual values with that graph block reader?​

VAG-com, or VCDS as we should now call it, can do almost anything that the VAG diagnostics computer can do, including expected vs actual readings.

Thanks for your help, do u need any other info?​

 

[spud31]

Bill

Where did you spray in it bill ?
Am intrested in doing it but i assume it needs to go after MAF so best place is through crankcase breather pipe on TIP?

Thanks

spud

 

[Ibiza2000]

I'd probably be taking a guess through where the inlet manifold is? Never heard of revive heard of ino tech, that goes straight in the turbo, which u need a kit for

Muttley, no smoke has ever come out of my exhaust (well a big puff of it anyway) and it doesn't now, which makes me think oil seals ain't gone or anything like that?

I spoke to mech a about the map, he said the turbo boost should kick in at 3200rpm, which Is weird as my car has always struggled to get to 3500 rpm and I'd b guessing the boost would take me above that, it used to be 2000ish rpm but he said that was too low for the turbo to spool which makes him think it's an electrical issue, This sounds worrying as u can imagine as the map sounds unsuitable, anyhow iv pushed it to 3300rpm and no boost was there, it's defiantly better at accelerating

It's due for a reading Thursday, mech a recons it's a boost pressure sensor, I don't know, what are my options to start looking at? (maf, vacuum hoses, n75 or other solenoid, temp sensors?) what would be viable to start eliminating first or most likely causes of my turbo not working?

Cheers

 

[Ibiza2000]

And thank you muttley u have more than showed me u have excellent knowledge of these kind of engines

 

[Muttley]

No smoke means the remap isn't radical, isn't overfuelling to produce more power.

You have a VNT turbo which is meant to provide boost from about 1500 rpm and full boost from about 2000. If Mech A says his map produces a kick at 3200 then it's been written that way. If he says 2000 rpm is too low for the turbo to spool ask him to explain how come the torque peak for the TDI engine is at 1900 rpm.

You should not struggle to get to 3500, you should be able to reach 4000 rpm without too much difficulty, especially in the lower gears.

By "boost pressure sensor" I'm guessing he means the MAP sensor (Manifold Absolute Pressure) i.e. the sensor that tells the ECU what the air pressure is at the engine inlet. MAP sensor failure will log a fault in the ECU and light the CEL, the engine-block "excess of pollution" light on the dash panel. MAP sensor failure would cause lack of boost.

 

[Ibiza2000]

Thanks again For the reply, doesn't a puff o smoke mean oil deals ina turbo are gone? There defiantly isn't any smoke, so what could that be pointing too?

As for the rpm issue lower gears are fine I try and feel it in third and forth but can't, it sounds like mech a doesn't quiet understand my turbo or engine :/ meaning mapping it would be very difficult :/ and further more if the map is writes for a boost at that sort of Rpm then I doubt it was what I was looking for for ina map, he did say tho it should boost at what it was boosting before which was 2000rpm ish,

Yea he means the MAP sensor, no light has come on, although I'd disconnected this before the vnts were cleaned, as it made my car perform better on acceleration (worryingly) as it was like driving a 100cc engine and also I disconnected my MAF the other day and there was NO performance difference - there are no warning lights aluminating at all for any sensors disconnected,

Any ideas from that or should I be getting worried now lol

 

[Muttley]

No smoke is not a bad sign. Just means that the remap is well written to avoid any smoke generation.

If the turbo oil seals start to fail you'll get significant oil smoke followed by turbo failure. The turbo spins very fast on a plain bearing which has a full pressure oil feed, so seal failure lets a lot of oil out. That's what I've read on here from those who've experienced it.

If the car drove the same with the MAF disconnected as it does with the MAF connected then it's a verry strong indication that the MAF is broken and needs to be replaced.

Mechanic A is worryingly inconsistent in his advice.

Has anybody near you responded on the VAG-com front? I think getting someone independent to log the faults and maybe reset them is a good first step.