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WK2 trashes its engine at 8 years old, 70K miles

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engine head gasket overheating
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4.3K views 13 replies 5 participants last post by  TheGrimmJeeper  
#1 · (Edited)
My 2015 WK2, Laredo, 6 Cylinder, 70K miles, trashed its engine yesterday. This was unnecessary and was due to the firmware not warning me about conditions that were logged in the engine controller and available via OBD2. This is how it happened.
  • I was camping at Lake of the Woods, Oregon. Without my knowledge, a stick pierced the radiator.
  • I drove down the mountain toward Klamath Falls. During this time, I smelled glycol (antifreeze) for a moment. Because I was going downhill, I figured this was uphill cars overheating.
  • The engine controller logged a coolant temperature "low" (actually high temperature, low resistance), but there was no dash notification.
  • I drove for an hour.
  • On highway 97 (the Volcanic Legacy Scenic Byway) I passed a truck on an uphill passing lane, accellerator floored. At this point there was a dash notification for "Electronic Throttle Sensor Needs Service".
  • The car started performing poorly.
  • I cycled through the gauges. The oil temprature gauge read "---.--". Oil pressure was between 20 and 30 PSI.
  • I limped the car to a rest-stop (Grass Lake, which qualifies as the middle of nowhere). Just as I parked, the oil pressure reached single digits.
  • There were visible fluids around the engine and on an attempt to start, white smoke was emitted from the engine. The engine would not start.
  • The coolant reservoir was full.
  • Torque reported 28 faults, including 2 camshaft faults, the overheat I should have been told about, and a bunch of seemingly unrelated body faults.
This vehicle will get a used engine. I'm annoyed, because this should have been simple radiator damage, had the firmware actually warned the driver about a coolant issue that it logged, and the increasing oil temperature. Instead, I lost the engine.

From hence, I am installing a separate temperature gauge and alarm, and not trusting the firmware. I'd install an oil pressure alarm if there was a good place to mount the switch.

I'm a reasonably competent auto mechanic and professionally I work in electronics and computer programming.
 
M
#2 ·
Just an FYI, if the coolant sensor isn't in coolant, it won't read properly. My take on this is that it leaked out of the system rather quickly so there was only a short period of time that it could of read hot. An aftermarket gauge will do the same thing if the sender is in the same location. The sensor is usually up higher so when the level dropped, it wasn't in coolant, so it didn't read right. If you do put an aftermarket gauge in, try for a lower position.
 
P
#12 ·
A lower coolant pipe clamp broke on a V6 Ford I had decades ago. 3 years old, 16000km from new. I did not notice anything and it possibly happened while my car was switched off while my wife went to a roadside shop (and WC!). She later said that there was a puddle under the car when she came back from the shop. The car started and drove normally (120-140 km/h) and then after some time lost power. I stopped about 200m farther and saw smoke coming off the plug wires. New heads, pistons, oil and water pump, rebore, the whole toot. Temperature gauge never moved from normal because it was not submersed in water.
 
#5 ·
This low-end feature badge "Limited" has the ability to display oil temperature or a number of other parameters, but only one at a time. I routinely have it on tire pressure. When I noticed problems, I switched to oil temperature and the display was "---.--". I then switched to oil pressure, and watched that fall to single digits just as I got to a safe place and turned off the engine.

The engine controller was obviously getting data about coolant loss and oil temperature, but apparently wasn't programmed to ring the bell and put up a notice, as it eventually did for the throttle valve.
 
#8 ·
Bruce Perens K6BP said:
The sensor, unfortunately, is at the top of the coolant loop and stops indicating when the coolant runs out.
Click to expand...
That's not correct. The coolant temp sensor is in the oil cooler housing/assembly, located beneath the intake manifold between the cylinder heads. If you are losing coolant due to a leak, the gauge will indicate the increase in temperature. But you have to keep an eye on it, otherwise having that gauge is meaningless.
 
#9 ·
The OBD2 log showed "coolant temp low" and that was the only coolant indication. I forget the number. I was thinking that this meant low resistance and high temperature, but maybe it really means low temperature. I didn't notice a problem on the gague, but I wasn't habituated to watch it as even towing on that rather challenging route and going up the infamous "Dead Indian Road" nearby never had a coolant issue.
 
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