Had one come in on the hook from another shop the other day and it left me with mixed emotions. I was humbled to hear the recommendations that brought this customer to our shop. My frustration was seeing the work that was sold to this customer that put this customer opinions of our industry in the negative. Grease on the seat, steering wheel, fenders and wheel.
Well the customer quickly realized that you get what you pay for. So this was a 05 Hyundai XG350. Customers complaint: Crank no start It was reported that the vehicle was taken to a local shop 2 weeks ago for intermittent misfiring and stalling that would restart after it sat. CKP sensor fault code "unknown P0???".
This vehicle was a runner, and the customer had been dealing with the fault for some few weeks as he was saving up the money for the diagnostics and repair. The timing belt was done at the local dealership almost 20k miles before this event. I must mention, no driveability concerns were present until the current fault.
The previous shop replaced the CKP (Crankshaft posistion) sensor and created the no start condition. Our local parts dealer later had mentioned they delivered at least 2 replacements for a defective sensor and rumored the previous shop tried another brand as well from another parts house. The customer had been getting frustrated as days went by and stated he witnessed the worst when he came in to check the status of his car. Long extended cranking while the engine was definitely struggling to crank. Cranking periods were so long the battery was needing a charger hooked up so it would crank. The car was pushed to a parking stall and there it sat.
After no activity with car for a few days, and the shop owner always telling a different story and theories, the customer searched for a resolution and started asking around where can he take his car to get repaired. This is how he heard of us. He pulled the plug on them and took a leap of faith and had it delivered to my shop. This was a filler ticket, as we were booked up for the next 5 weeks. The customer was prepared that it may not get diagnosed for a week or two because of our current workload and was ok with it. After I heard all the details to this ticket, I pulled off a chance to get out to the car to identify the customers complaint. It was then I realized the work of this so called shop as mentioned earlier, missing engine cover, greasy fingerprints all throughout, including grease on the seat.
Ok now the good stuff! Labored cranking, weak battery charge. I performed some quick visuals and put the battery on the charger. Let me specify labored cranking as a definite timing issue is unmistakable. It wasn't till the next day I was able to actually take a crack at it. After letting my mind soak all the gathered details, I chose to hit this one with my fastest approach: CKP/CMP correlation reading. I chose this test for the reasons of time, the convenient location of the harness, and the reported original fault, over the test of in-cylinder pressure readings with fuel and ignition control syncs. I would have came to the same results in the end, and honestly regret not getting a capture of that strategy just for personal records. I just didn't have the time to get it. The attached images show the results of the waveform captures as well as the parts damaged. They also include the new replacement parts and the final waveform proving the fix. As I was preparing the morning before the the diagnostics, I gathered the waveform capture
I searched the library for a good known capture on the XG350 and no Images were found, so I looked under a Santa Fe 3.5 of the same yr and found a match knowing that this is the same engine.
Within Less than 30 minutes I had enough evidence to perform a tear down inspection. I stated in my report specifically that the timing was indeed off but need to verify mechanical timing and/or pcm inputs were off do to ckp reluctor damaged. Again, I would like to note an in-cylinder pressure reading would have narrowed this down to a smoking gun but at this time I went with my gut and needed not to go into more diagnostics. Knowing this design of engine and the location of the CKP sensor, I thought that the reluctor would be my best smoking gun because the belt does not need to be released for replacement of the sensor as stated in the last repair. I pulled it in my bay and pulled the balancer off... BINGO. My gut was right and I got to do my happy dance! Just about an hour on the clock and I was able to do diagnosis and a tear down of the timing belt to inspect damage to the crank gear and reluctor.
After pulling off the gear and writing up the repair order, we gave the previous shop a call to see if they would be willing to correct their mistake and gave them the option to buy the parts at our cost with our sublet labor prices. They declined stating they never removed the balancer and this was a preexisting condition. Seriously??. The car drove in, and after the repairs, was a no start condition!!
Let me explain what I'm pretty sure happened for those who have never witnessed this, so that it may be prevented: On some makes and models the balancer is not aligned on the crankshaft with a key way, but instead, secured on more of the front face of the crankshaft and the timing gear with a roll pin as an alignment guide. These roll pins can and do rust, and can make the balancer difficult to separate. With the little extra force that is needed to remove the balancer pulley, the timing gear will move with it, causing the reluctor to snag on the CKP sensor pulling it off the back of the timing gear, which is held by two smaller roll pins.The key way slot cut in the crankshaft does not continue all the way back to the flanged face of the crank, so when the reluctor does come free, it can spin and can be missed if not checked. Then, as the engine is reassembled and not checked, it will get secured in it's new position causing the PCM inputs to be off time. I've seen this far too many times; from a slightly off mark, to one as bad as this 3 teeth off. Again, it’s mechanically spot on.
As a trick for preventing this, when I personally identify this design, there is a hole in the front face on the balancer pulley, sometimes behind the torque washer. After removing the crank bolt and that hole is visible, spray a penetrating oil in there and then grab a roll pin punch. Stick it in the hole and give it a little love tap, it doesn't take much. Then remove the balancer. Still check before and during the reassembly process. Save yourself and possibly the next guy the grief of chasing a drivability issue later. Also just as quick note, these Hyundai motors should get a new crank bolt when removed. Reusing them will be putting yourself at risk for a bigger problem. They do stretch under factory torque specs and can break, even months down the road. Last man in is responsible, so keep that in mind. I know most of you may be aware of what was just mentioned and forgive me if it came across insulting, but I'm hoping to give a little insight to those who may not be as experienced. It's just this particular ticket could have been prevented, and I'm frustrated with shops and techs not taking responsibility for the mistakes when made. Own it!!! The parts sold in the end were a new timing gear assembly, crank/balancer bolt and a LOF. The reason for the oil change was the shop continued to crank the engine so long it washed the piston rings and contaminated the crank case oil. Removing the oil cap smelled like it was a fuel tank.
So after all said and done, it took a few minutes for the plugs to fire correctly and to allow the rings to seal. Misfires where expected and did clear up. As far as possible damage to the converters, it’s been noted on the final write up that premature failure is likely due to excessive exposure to raw unburned fuel.
Here is a shot of the capture after the parts replacement.