[5Ogenny]

Hello everyone, I have a 2012 Santa Fe 2.4 MPI with 112k. This vehicle has been a reliable vehicle since new. A few weeks ago the vehicle started to have a knock at idle and I found metal in the oil. After calling Hyundai and finding out that the 2.4l MPI motors are covered like the 2.4 GDI. Searching for good replacements engine I found a rebuilt engine for a reasonable price. So I went ahead and ordered it. After receiving it, me and a friend removed the old engine and swapped the parts (Expect for the oil control valves which were provided by builder) we had to the new rebuilt. After installation on the rebuilt. The engine starts fine and idles good.

On its first test drive the vehicle drove fine under low rpms. Once the vehicle goes to 3000 rpms, the esc and down hill assist lights will come on. The rpm tach will shut off and the vehicle will run rough. After shutting off and restart of the vehicle runs okay till the condition at 3000 rpms occurs.

A code scan got me a for p0336, p0014, p0079. First I thought the engine is out of timing but after poping off the valve cover and rotating to TDC the engine is timed okay. We actuated the oil control valves, they seem to be working. Then visually inspected of the Crankshaft position sensor the wiring at connector looks good. Now I’m kinda lost on how go with diagnosis this issue. I don’t want to throw a Crankshaft position sensor at it unless I need too.
Any tips on how to further pin point the problem?

 

[AUTOSPARK]

Any tips on how to further pin point the problem?

The tach dropping out suggests there is an issue with the crank position signal. What I would do is backprobe a voltmeter across the crank sensor power supply terminals and monitor the voltage during a test drive to see if the supply voltage is dropping out at the same time as the tach does. To ID the power supply and ground wires on the sensor connector simply disconnect the sensor, switch the ignition on, and measure the voltage on each terminal of the sensor's harness connector. The power supply terminal will have 12V, the signal terminal will have about 5V, and the ground terminal will have 0V. Back probe the meter between the 12V & 0V terminals and reconnect the sensor.

If I helped you fix it, why not...

Your support is greatly appreciated​

 

[5Ogenny]

Yesterday I checked Singal of the crankshaft position sensor using a oscilloscope. I got a good reading at idle but once the vehicle got to 3000 rpm the tach went out and signal periods increased. The same the engine ran rough. P0336 appears as history code. I believe the voltage of signal when using the oscilloscope was 5V.

 

[AUTOSPARK]

I believe the voltage of signal when using the oscilloscope was 5V.

Did you connect the scope at the sensor or at the ECU?
The 5V signal voltage comes from within the ECU. If you connected the scope at the sensor and got 5V you know the wiring between the sensor and the ECU is good.

Did you measure the supply voltage at the sensor as I suggested to see if that is the cause of the signal drop out?

If I helped you fix it, why not...

Your support is greatly appreciated​

 

[5Ogenny]

When I used the oscilloscope I tapped into male end of connector of the sensor and female end of the harness.

I was hesitant to replaced the crankshaft sensor because of how expensive it was. But I entered the part number into amazon and found for the quarter of the price from the dealer. It’s stated it was OEM. So I purchased it and installed it today (Monday). That seem to be cause of the issue I’m was having. The part did look different then the part I pulled out. Part number match, so I guess Kia/Hyundai must of updated the part over the years. I have no check engine and I able to accelerate over 3000 rpms again. I’ll keep updating the thread for the next few days.