[nzenigma]

Hi Mike,

This will give you a heads up on the Common Rail system. The concept is basically the same with all. http://www.yildiz.edu.tr/~sandalci/dersnotu/AKTraining.pdf

Re the scanner. The ebay one is fine. All you want is to read data, trouble codes and to erase them. Assume you have none???

Your mechanic is correct about letting the turbo idle so that it will cool down and wont fry the lubricant sitting in it. But, they are not a high performance turbo and the average Joe forgets ( self included), and they rarely fail, otherwise the i30 would have a timer as standard equipment.

The sensors are worth a check but MAP is probably reading the lack of boost correctly.

"There is that vacuum actuator on top of the turbo, which looks like it might divert exhaust gases around the turbo, thereby controlling it's operation, but I can't get a good look in that area. Anyone confirm that?"

The actuator is opening the fan veins to allow the turbo to spin. As I said before, forget the keyboard warriors who are repeating stuff they have only read about wastegates.
This is how the i30 turbo works.
Stop screw adjustment - adjusting Turbo VNT stop screw

The mechanic has fitted your old turbo that was working ok??????? so its probably not the problem. Hopefully he didn't get desperate and start adjusting it.

The ECU gets data ( from the MAF sensor among other things) and is pulsing a turbo vacuum control valve to open part way or fully. {trace lines back from the actuator to find it} When vacuum can reach the actuator, it pulls up, fan shape changes and boost begins.

As said before not much has changed. The motor is mechanical, it will go or stop. So think about what would heat affect = electrical components, GASKETS (manifold???) rubber hoses will split or suck flat with vacuum. Check sensor on top of intercooler RH beside the Rad.
Cheers G

PS. the turbo operation is delayed by a temp sensor for cold starts..Explore!

[tw2005]

I think generally if I've come straight off the highway and pull up I'd let it idle a bit or if I had been racing but mostly I cruise into home at a gentle pace and turn it off within 30 secs or straight away. No issues and 211000 k on this thing and not a hint of any issues in fact it runs better and quieter than the wagon setup with around 60000k.

here's a question , what does the user manual say?

[diesel1984]

All you can do is to take a few pictures of engine and post them here. Then someone can  tell you if somethig is wrong connected. Vac system is very easy on this but yes you can mess it.

[Mike8]

Thanks NZ, you are right, no codes popping up, and yes, the old turbo is the same one now, and was working fine, a definite kick in the pants from 1500 rpm every time. I have traced the vacuum hoses from the vac pump to the three way solenoid valve, and back to the vacuum servo. I did figure out that the turbo is called a VGT, or Variable Geometry Turbo, so I figured that the servo must change the blades, or the flow around them. I also fitted a tee piece in the line to the servo,and ran a vac tube into the car, and then connected a vacuum gauge. Then, on a test drive, saw that when there is no vacuum, I have no turbo boost, and when it has vacuum on it, I get good boost. So I have ruled out the turbo itself. Now I want to run a small twin cable from the solenoid valve to an LED in the car, so I can see what electrical signal that solenoid is getting. I have found from the manual that it's a PWM signal at about 300 Hz, so I should see a varying brightness of the LED as it modulates. This is beginning to indicate that the ECU is controlling the turbo, as it should,but now to discover why. What has changed, or what is changing, that is causing the ECU to put the brakes on the turbo? And that is where I feel the GDS scan tool may provide more information. The only other possibility that it is a mechanical fault, is the vacuum pump that came on the new motor.... maybe it is not not pulling a constant vacuum. But I'm also bending away from that theory, because every time it has the low power/no boost problem, I can take my foot off the gas, and then put it down again, and then I get full turbo boost, which is born out by the reading on the vacuum gauge.

I also looked at the MAF sensor, couldn't see much, and it's well protected, and it is showing good response to the accelerator pedal on the scan tool. The MAP sensor only senses atmospheric pressure, and is built into the ECU, but the one that matters is the Boost Pressure Sensor (yes, a bit confusing, because that's the one I/we usually refer to as the MAP or Manifold Absolute Pressure Sensor). When I took it out, it was covered in black engine oil. I have noticed previously when servicing the car, and I've taken the air inlet hose off the turbo to access the fuel filter, that the inside of the turbo always has a thin film of engine oil on it. Another mate who is well into turbo 4WDs, told me that is quite normal. I checked with the manual, and it seemed only concerned with "is it covered in carbon deposits", no mention of oil. I attempted to test it on the bench with a 5 volt supply, and then measured the output from Pin 1 while I varied the pressure on it, but got an expected voltage, which didn't alter with pressure. When I went to fit it back into the car, and checked voltages there, I realised that the terminal numbers on the sensor,were opposite to the numbers shown in the manual, and I had it connected wrongly on the bench. Fortunately, it does not appear to have suffered any ill effects, and still outputs correctly and reports the temp and pressure correctly. I'll watch out for that in future, if I decide to test a component off the car. Don't believe everything you read in a manual!

That's all I have to report for now, will let you know what else I find,although it maybe a few days before I get time to do much,back to work Monday tomorrow

[nzenigma]

@Mike8 . Doing well mate, as per our training. Working logically using critical thinking. 

I have been thinking about your problem, we need to go back to the start and work forward. There is one factor you seem to ignore and it has been bugging me,  I said this sounded like finger trouble,  its your mechanic -    Sorry.

He was given a vehicle that, apart from chain rattle, drove fine.
He returned said vehicle with new motor and said it drove fine; it didn't.
He then found codes  ; was he using the borrowed scanner ????; he should have a basic OBD2 reader at least like your ebay one. If not why?
Did he read current or ancient codes? Did he clear them, did they return?
He changed the fuel filter that was functioning ---- ok not a major crime.
He swapped your fuel control valve and said problem fixed  , returned car, a turbo/vacuum fault remains.

So you need to understand your mechanic's activity.
Consider the likelihood that you have, or HAD, 2 different faults...under the circumstances, highly unlikely

refit the original control valve and see if codes reappear?
If no codes...he was full of BullS
If there are codes, what else has he cocked up?
It is possible that he was dicking around with a full workshop scanner, which can alter the ECU and other data settings.
Not used to it, he has changed a function. For instance, did he tell your car it is an automatic?

A very small amount of oil in the turbo to cooler line is normal, it is from the turbo bearings.

Cheers 

[Dazzler]

@Mike8 As long as you are in the habit of doing a good (say 50km +) highway drive at least once every couple of weeks the DPF won't be a problem.   

[diesel1984]

@Mike8 . Doing well mate, as per our training. Working logically using critical thinking. 

I have been thinking about your problem, we need to go back to the start and work forward. There is one factor you seem to ignore and it has been bugging me,  I said this sounded like finger trouble,  its your mechanic -    Sorry.

He was given a vehicle that, apart from chain rattle, drove fine.
He returned said vehicle with new motor and said it drove fine; it didn't.
He then found codes  ; was he using the borrowed scanner ????; he should have a basic OBD2 reader at least like your ebay one. If not why?
Did he read current or ancient codes? Did he clear them, did they return?
He changed the fuel filter that was functioning ---- ok not a major crime.
He swapped your fuel control valve and said problem fixed  , returned car, a turbo/vacuum fault remains.

So you need to understand your mechanic's activity.
Consider the likelihood that you have, or HAD, 2 different faults...under the circumstances, highly unlikely

refit the original control valve and see if codes reappear?
If no codes...he was full of BullS
If there are codes, what else has he cocked up?
It is possible that he was dicking around with a full workshop scanner, which can alter the ECU and other data settings.
Not used to it, he has changed a function. For instance, did he tell your car it is an automatic?

A very small amount of oil in the turbo to cooler line is normal, it is from the turbo bearings.

Cheers 

Auto mechanic who is working in 2017 and doesn't have OBD diagnostic equipment?? 
I don't get this guy how he run his business?



I'm not mechanic but I have diagnostics for various types of vehicles that I own.
For this hyundai-kia I own Carmann and Hi-scan with programming options.

[nzenigma]

That's because you can buy them for.......20-30 euro   

[Mike8]

Hi again, NZ and Diesel, sorry I wasn't around last night, I was busy with a Taekwondo grading night, and that was followed by "the boss's dinner". I didn't get home till midnight, in bed by 12:30, and up for work again at 0400! I tell you, it took all of 3000 bar to fire my injectors this morning.... still don't know how I got through the day.

Thanks for comments, but let me explain a little more about my mechanic. He owns a straight line drag race car, not a dragster, but a big supercharged V8 with a driver's seat behind it and a car body dropped over the top of both. It is pretty successful, and he appears to know engines and cars fairly well. He told me he had been a workshop mechanic for several different employers back in the 70s and 80s, before he started work at the site where I now work. He has also done other similar jobs to mine, in that he has bought cars very cheaply with major problems, and he's sourced an engine or transmission at the right price, and put them together to make a good car that he has either passed on to his family, or sold for a modest profit.  However, those jobs didn't necessarily make him an expert in either Diesels, or modern computerised cars. His very good mate, who I also know, and is the driver of his race car, owns a scanner that he has used just for trouble codes when he's needed it up till now. He also borrowed another one from another mechanic mate of his, when I took the car back to him, and he did the replacement of that component on the injector pump,which I think is referred to as a fuel press regulator. But I doubt that he would have had a programmer, or made any alterations. He certainly gave me the impression that he wasn't the type to make changes "willy nilly", or make any changes or adjustments that he knew nothing about, unless he had very good advice. As far as not having his own, he seems to have gotten away with borrowing one up till now, as indeed I myself have up till now. But I'm fairly sure he would have ordered one himself by now, he seemed rather smitten with mine.

One of the reasons I am considering buying the GDS system,is that it gives a lot more information than my current scanner, AND it allows you to place the ECU into "component replacement mode", where the ECU will "learn" the characteristics of a new part like a sensor,and trim it to best suit the suit the engine and driving conditions. I feel my current problem is due some little mismatch in a part,which could even be the aforementioned regulator. I also feel the problem may be slowly fixing itself, by the computer slowly re-learning it's characteristics, as I'm not finding it a noticeable. Either that, or I'm getting used to it.

Anyway,my eyes are almost falling out of my face now, so I better get to bed.

Cheers all, Mike.

[nzenigma]

You could do a basic re-learn by disconnecting the battery over night. Good luck.

[Mike8]

Hi all, I think I've finally found it.... and fixed it! A small vacuum leak! Yes, NZ, you were right..... I guess I can blame the mechanic,but I'm not.

First, I fitted a pressure transducer to the vacuum line to the turbo servo, and an LED on the solenoid that controls it, and found that if vacuum dropped below about 30-32 kpa, I had practically no boost until engine revs picked up past 3,000, and above 40 kpa of vacuum (or -40kpa pressure), turbo boost was normal. After a lot of driving around with it,I still couldn't make "heads nor tails" as to why sometimes the vacuum would fall away, and not comeback. Then I changed the transducer to the vac pump line, and found it was as erratic as hell, in fact it behaves more like manifold vacuum on a petrol engine, the faster the revs, the lower the vacuum, and at idle, vacuum is highest. I presume that cylindrical item at the end of the intake camshaft is a vacuum pump.... so then on Sunday morning, I connected a second transducer up, so I had one on each tube, and could watch them simultaneously while driving. I had to drive for a good half hour before the vacuum dropped enough to cause the boost problem, and then still had no answers. Then, this morning, on the way to work, it hit me, I could see the vacuum drop off very slowly with steady driving and that turbo control solenoid apparently closed. Under certain driving conditions, mainly pumping the accelerator, that valve would open momentarily, and allow more vacuum to the actuator. But then the vacuum would slowly drop off again, like over a couple of minutes, and that is when I had no boost.

After work this avo, I pulled all the hoses off the steel tubes,and polished the steel with fine steel wool, applied a slight smear of vaseline to each tube and pushed the rubber tubes back on. I then started the engine, let the vacuum buildup to 61 kpa,then applied a pinch off tool to the rubber tube between the solenoid and the actuator, then turned off the engine. I came back an hour later, and the vacuum was still at 56 kpa, a huge advance on how fast it was dropping off while driving. I took it for another drive,and it has been great, no sign of losing vacuum there, or losing turbo boost, so finally, by checking and testing, and slowly getting closer to the problem, I finally snuck upon it and beat it!

In either two or four weeks time, I'll be heading down to Brizzy, and really looking forward to giving her a decent run. This engine is certainly not lacking in power, I'm very happy with it. And now, I'll have to start turning my attention to the timing chain in the old one.

[nzenigma]

@Mike8
Brilliant Mike.  I may have been right , but it was your persistence and methodical fault finding process that won through. 

To give you further praise; I get really frustrated that your practical hands-on skill and ability to think critically is rarely evident in today's society.

Best wishes , Gary

[mickd]

Great stuff mike,
Most times the simplest take the longest to find.
Thank goodness for cable ties eh ,   

[Mike8]

Yeah thanks Mick, I love cable ties,except most of the time when I want them, I can't find the right ones!

Hi Gary, yes, I do prefer to "nut out the problem", rather than just try this and that and using trial and error, and never really knowing what fixed it, or worse, not fixing it at all. I think it's a part of my 60s, 70s and 80s upbringing. It's sure a good feeling when you finally "hit the nail on the head", even when it is one of the simplest fixes.

Now I'm looking forward to driving down to Brizzy in a few weeks, as that is what started the saga. I was heading down there a few weeks back, and before leaving, dropped in on the mechanic to give him a listen to the noise..... and this is how it ended up!

Cheers,

Mike.

[tw2005]

Yeah thanks Mick, I love cable ties,except most of the time when I want them, I can't find the right ones!

Hi Gary, yes, I do prefer to "nut out the problem", rather than just try this and that and using trial and error, and never really knowing what fixed it, or worse, not fixing it at all. I think it's a part of my 60s, 70s and 80s upbringing. It's sure a good feeling when you finally "hit the nail on the head", even when it is one of the simplest fixes.

Now I'm looking forward to driving down to Brizzy in a few weeks, as that is what started the saga. I was heading down there a few weeks back, and before leaving, dropped in on the mechanic to give him a listen to the noise..... and this is how it ended up!

Cheers,

Mike.

Seeing all that test gear, I'm getting aroused. something tells me maybe you would have been better doing this job yourself.

Depending on what was yours and what came with the motor I guess easy to transfer a fault too.

when I did my transplant I had the whole car so it was quite evident the damaged area (frontal) so i paid close attention for anything damaged.

Those vacuum lines to the solenoid and turbo were also damaged including the solenoid itself, then the intercooler hose was split as was the air pipe to the turbo, the swirl flap motor. Nearly missed the intercooler hose, small split underside only discovered when i was double checking fit and security .

A good tech always goes searching for evidence, sometimes you have to take a punt though. 

[diesel1984]

This is a hell of a way to find and clear a fault code.
Not a everyday procedure.
Why didn't you test vac lines first for a split or leak with vacuum tester?
You could also test VNT with cav pressure pump



Very nice that you sorted it in your own way.