Timing chain, belt or tensioner failure on the 2003 Kia Sorento
When timing chain, belt or tensioner failure gets reported
Owners of the 2003 Kia Sorento report timing chain, belt or tensioner failure at a median of 65,000 miles. A quarter of the reports come in before 45,000 miles and a quarter after 80,000 miles, from 19 reports that carried an odometer reading.
A part like this is normally expected to survive 120,000 miles. It is the 4th most-reported problem on this model year.
The mileage distribution
The reported range runs from 35,000 miles at the tenth percentile to 90,000 miles at the ninetieth, a spread of 55,922 miles across the middle 80% of reports.
Reports bunched into a band this tight usually mean the component has a life of its own: it goes at roughly the same mileage regardless of who owns it.
0% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 36,000 miles | 42,989 miles | 63,333 miles | 79,000 miles | 91,922 miles |
Read the 10th percentile as “one report in ten arrived this early”. Exact figures are shown in this table because it is the table of record; everywhere else on the site they are rounded to the precision the sample can carry.
What a percentile can and cannot tell you here
These five numbers describe the readings owners gave, in order. The median is the middle one: half the reports arrived below it. The 10th and 90th are the edges of the bulk of the distribution, and the distance between them is the part worth reading. A tight spread — say 70,000 to 95,000 miles — points at something that wears out on a schedule, and the schedule is knowable. A wide one, 20,000 to 190,000, points at a fault that hits some cars and never troubles others, which means the mileage on the listing in front of you tells you very little about your odds.
What these figures are not is a survival curve. Every reading here comes from a car whose owner filed a complaint, so the sample contains only failures: it cannot say what share of the fleet made it past 150,000 miles untouched, because those owners had nothing to report. Nor is the mileage the moment of failure — it is the odometer reading as recalled at the time of filing, which may be weeks later and is sometimes rounded to the nearest ten thousand by the person typing it.
Percentiles are shown at all only once 8 readings exist for the vehicle and mode. Below that the middle of a handful of numbers is noise wearing a decimal point, so the figures are withheld rather than dressed up.
What happens, and what it costs
Putting it right typically runs $1,200–$4,500 at an independent US shop. That range is an editorial estimate held in this site's failure-mode catalogue, not a figure from NHTSA, and it is a repair cost rather than a diagnosis cost.
This mode is classified as critical, which means a failure can leave the car unable to stop, steer, or stay out of the way of traffic. It is weighted accordingly in the risk score.
The same failure on other years
The same failure is reported on 9 model years of this car. It shows up earliest on the 2014, at a median of 40,000 miles, and latest on the 2011 at 120,000 miles.
By volume the 2006 carries the most reports, with 23; the 2003 has 20. A mode that appears across most years of a model is usually a design choice rather than a bad batch.
If one year stands out to the left, that is the year to avoid; if the whole line sits at a similar mileage, this is wear rather than a defect in one production run.
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
What owners wrote
Verbatim from NHTSA complaint narratives, trimmed for length. The mileage is the one the owner gave.
As I was driving down the freeway, the engine stalled and all lights on the dash came on. I was able to pull to safety (just by sheer luck) and called kia 1-800 for towing service. The vehicle was towed to an authorized dealership. I was initially told that the timing belt was malfunctioning. Supposedly the analyzer showed that there were "multiple misfires. I was asked if the car was missing prior to the stall. I told them it ran as smooth as silk. I authorized them to replace the timing belt despite the fact that it had been replaced as part of scheduled maintenance two months earlier. The dealership then called and told me they had "good news and bad news". The timing belt was repaired but it appeared the head was blown and that kia refused to pay for repairs because the overflow bottle was cracked. They stated that the head blew because the engine overheated and was caused by my negligence. The gauges never indicated that the car overheated. They are unable to tell me how much the repairs will cost because there may be further damage once they tear it down. The estimate is between $2500 and "wore case scenario" $4700 I am…
"the battery and brake lights were on the dashboard. Also, the vehicle lost power steering. Opened the hood and the engine area and found the alternator belt fell off its pulley. The power steering belt ran off the alternator belt. This was why the vehicle had no power steering. Checked the crank shaft pulley, and found the crank shaft pulley had play, and the crankshaft bolt backed out of place. Kia has a pit stop highlight , stating that the crank shaft bolt backed out of place due to improper torque settings on the crank shaft bolt. Highlight kt2006042501. Removed the radiator to gain access to the crank shaft pulley. Removed the crank shaft pulley and inspected. Found the crank shaft sprocket pin sheared off due to the crank shaft pulley backing out place. The crankshaft sprocket holds the pulley in place. The crank shaft pulley, sprocket, and bolt will have to be replaced. Removed the timing belt and to replace the sprocket. Installed everything back in place and started the vehicle. Oil was now leaking from behind the timing cover. Removed all parts again to gain access to the timing belt. Found oil was leaking from behind…
Last feb. The coolant reservoir cracked, lost all coolant. Towed to dealer. They fixed it and told me that I needed a new belt. I didn't want anything more to happen as I take my 90 year old mom around, they replaced one belt for $120. Never ran right after that, with screeching noises and no more A/C. Today, just as I was driving onto the highway-I started losing my steering and I immediately pulled over off the ramp, then it stalled as I was pulling over. I have read about this happening to a lot of people and was just waiting for it to happen. Well it did and thank god I wasn't going 70 on the highway yet. It has been towed to dealer and they said it was the bolt on the drive shaft that broke. Then he said that since I'm only 8000 miles away from 60k, then I should just do the timing belt service now because if I don't and it goes, then my engine will blow. So I guess this is what I have to wait to happen next and I'm sure it will. Thousands of people can't be wrong. Don't buy a kia!!!!!!!!!!!!! *tr
Also reported on the 2003 Kia Sorento
Other engine problem
Fuel tank, filler or EVAP failure
Other fuel system problem
Other steering problem
Other electrical problem
Airbag warning light or occupant sensor fault
How far this goes
Complaints are voluntary, so 20 is a floor and not a count of affected cars. Mileages are typed in by owners and cluster on round numbers. And the mode itself is assigned by software reading the complaint text, which is reliable in bulk and fallible one report at a time.
Questions this page answers
At what mileage does timing chain, belt or tensioner failure happen on the 2003 Kia Sorento?
Across 19 owner reports that included an odometer reading, half were filed by 65,000 miles. A quarter were filed before 45,000 miles and a quarter after 80,000 miles. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is timing chain, belt or tensioner failure on the 2003 Kia Sorento?
20 reports have been filed with NHTSA, about 6.8 per 1,000 vehicles. Complaints are voluntary, so this is a floor rather than a count of affected cars.
What this is and is not. These are the mileages at which owners chose to complain to a federal agency, which is not the same as the mileage at which the part fails on every car. It skews toward failures that happened outside warranty, cost real money, or frightened someone. It is still the only public dataset that carries failure mileage at all, and the shape of a few hundred readings is informative even when a single one is not. Methodology · JSON · this failure on other cars
Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed