Intermittent noise, black smoke, power loss in 2005 Kia Sorento CRDI

[taxo_p]

Good day po! I need your opinion before I go see a mechanic. I have owned a 2005 kia sorento crdi for more than two years now (bought 2nd hand) and our ownership experience has been great so far. For its age, it has not given me any serious problems until recently. Some strange noise appears intermittently followed by a loss of power and black smoke coming from the tail pipe. The noise seems to be coming from behind the dashboard in the passenger side. Ang tunog nya ay parang motor na na-stuck at nahihirapan umandar.

At first I suspected that it had something to do with the blower, aircon, or the recirculation motor but the sound would not go away even if I turned off the aircon, fan, and re-circulation. Later I noticed that black smoke would come out the tailpipe when I revved the engine. There was also a significant power loss when this happens. Hirap na hirap humatak. The few times it has happened, I was not in a position to pull over and check where the sound was really coming from. What I know is that if I turn off the engine and restarted, the problem would disappear. The sound also does not appear to depend on how hard the engine was revving. Steady lang yung sound whether apakan ko yung accelerator or not. A few days ago i tried driving around where I could pull over anytime. I wanted to replicate the problem so I could check where in the engine bay the sound could be coming from but I could not trigger the problem. Then it happened again earlier today while I was driving along slow traffic. I couldn't stop at the side of the road because I did not want to cause more traffic. Because the traffic was slow enough, I just turned off the engine and restarted it again. Normal na ulit ang takbo after ko mag-restart until about 30 mins later. Turning off the engine solved the problem again.

Because the sound comes with the loss of power and black smoke, I'm thinking it may actually be coming from the turbocharger. The turbo is located at the passenger side of the engine bay which may explain why it sounds like it's coming from under the dashboard. Is my turbocharger starting to fail? Meron po ba sa inyo na naka-experience na ng ganito? If yes, ano po ba ang repair/solution dito. Sana po ay hindi sobrang mahal ng repair. Dadalhin ko sa mekaniko sa tuesday pero gusto ko po sana na makakuha muna ng opinion dito.

Salamat sa mga mag-rerespond.

[barako ba ma]

Is the MIL on when the symptom persist? Is the MIL flashing when it does not have power? Have it scanned for ,DTCs first.

[taxo_p]

The MIL/check engine light did not turn on. There were no error codes, at least none that my bluetooth obd scanner can read. I inquired with several mechanics and most agreed that is was the turbo getting stuck intermittently. I searched around the internet and found a shop in banawe that repairs turbochargers. I called them up and asked for a quote under the worst case scenario. They said that it would not cost me more than P18k. In the end i had it repaired/rebuilt for P16k.

According to the mechanic who worked on the turbo, the shaft was getting stuck due to carbon deposits in the internal components. I was able to observe most of the work that they did except for a short time when I had to leave for lunch. I did see them disassemble the turbo and clean everything up. There was a bit of sanding done to clean up some parts. Pinalitan din "daw" nila yung seal rings. I wish it wasn't so expensive but at least it worked. I heard that a surplus turbo would be around P20-26k not including the labor for installment.

I haven't encountered the same problem for about 2 weeks now so I guess it really worked. I hope I did not make the mistake of choosing the cheaper option.

[niky]

The MIL/check engine light did not turn on. There were no error codes, at least none that my bluetooth obd scanner can read. I inquired with several mechanics and most agreed that is was the turbo getting stuck intermittently. I searched around the internet and found a shop in banawe that repairs turbochargers. I called them up and asked for a quote under the worst case scenario. They said that it would not cost me more than P18k. In the end i had it repaired/rebuilt for P16k.

According to the mechanic who worked on the turbo, the shaft was getting stuck due to carbon deposits in the internal components. I was able to observe most of the work that they did except for a short time when I had to leave for lunch. I did see them disassemble the turbo and clean everything up. There was a bit of sanding done to clean up some parts. Pinalitan din "daw" nila yung seal rings. I wish it wasn't so expensive but at least it worked. I heard that a surplus turbo would be around P20-26k not including the labor for installment.

I haven't encountered the same problem for about 2 weeks now so I guess it really worked. I hope I did not make the mistake of choosing the cheaper option.

All things considered, 16k was not bad. You could spend up to 30k on a turbo rebuild.

Congrats. Hopefully it won't recur again!

[mckeinley]

Yun din sabi ng papa ko pag black smoke isa sa pwedeng dahilan yung carbon deposits na kelangan linisin at tanggalin.

[taxo_p]

Here is a long story and finally a resolution to the problem.

So I had the turbo rebuilt but the problem returned in a little less than three months. I returned to the shop for warranty work. Being confident in his work and that the turbo should have no problems after the first time he worked on it, the mechanic suggested the problem might be caused by something else. He was suggesting faulty injectors but I find it extremely unlikely since it does not explain the noise coming from the front passenger side of the engine bay. I was also suspicious that he might be trying to come up with some reason to get me to agree on additional work on the vehicle where he can get paid instead of the warranty work that would have been for free. Since we could not replicate the problem (only happens every few months) it was very difficult to do a diagnosis. Anyway, he quickly agreed without much negotiations to reopen and clean the turbo again.

A few months later, the problem returned again. At this point I was almost sure the problem was in fact being caused by something else. I thought, what else could cause loss of power and black smoke in a turbocharged diesel engine? It has to be restriction in the air flow. If it wasn't a sticking turbo, I thought it might be the anti-shudder valve. I did some reading on how the anti-shudder valve works and started suspecting it might be the anti-shudder valve solenoid that's malfunctioning. The solenoid is on the same side of the engine bay where the turbo is found so it might have been the source of the noise. So I came up with a plan on how to do a diagnosis but had to hope that the problem recurs at a time and place where I could safely park the vehicle and look into the engine bay without turning off the engine.

A few weeks later, the problem resurfaced while I was driving only a few meters away from a gas station. I was able to park in the gas station and looked into the engine bay. After giving the solenoid a few hard taps the noise disappeared. I also looked underneath the engine cover and sure enough the anti-shudder valve was in the closed position. Diagnosis solved.

I have replaced the solenoid last December and the problem has not returned since.