Hey guys, I'm kind of at the end of my rope here.
A couple background details. I'm not a mechanic, but I've been wrenching on cars since I was a kid. I'm almost finished with a complete restoration of a 70s Ford, I went to college for mechanical engineering, and I've done a lot of construction over the years including flipping some houses on the side doing most of the work myself. So, not a mechanic, but a pretty capable guy.
I recently purchased a 2016 Land Rover LR4. I wasn't looking for a LR specifically, but just a decent larger family car for an extra winter vehicle for cash mainly. I was told at the Used Car Dealer they had replaced the thermostat while it was in their possession. On the drive home I threw a CEL. It was lean bank 1 & 2, and Low thermostat temp readings. After some research I replaced the PCV valve and the little elbow thing in the cooling system with the upgraded brass one because I found it leaking. Cleared the codes, drove it. Threw a CEL, just one of the banks was lean and a low thermostat temp. Decided to change the thermostat. When changing the thermostat I found a vacuum line on the drivers side (US) underside of the air box was not connected. Replaced the thermostat, which I think was never actually replaced by the dealer, replaced the hose that has the plastic press fit deal on the bottom of the thermostat. Put the whole thing back together. Vacuum filled the coolant and put all the vacuum lines on. I drove it on and off for a couple days (maybe 40 miles total) with no issues, no CEL, runs amazing with everything working properly. Take a trip to Cincinnati, OH about 300 miles round trip. Runs great, no CEL, zero problems at all. Slight coolant smell when we arrived in Cincinnati, which I expected because all the coolant I was able to coat the engine with while chaining the thermostat. After the trip and the drive home barely any smell at all which made sense. The whole time I hadn't seen a drop of coolant, no issues at all. Park in the garage all is good. The next day I go out, coolant under the car. The coolant level was at the max cold fill level when I closed the hood after the work I did, it's just below the low level line now. So I top it off again and decide to drive it short distances for a few days to try and find the leak. several trips, no leaks, on the 5th or 6th trip park it in the garage and the next day coolant on the floor. I decided to pressure test the coolant system even though it held a vacuum when I filled it I figure pressure is different than a vacuum so we'll see where the leak is. I pressure test it for 25 minutes and not a drip of coolant anywhere no loss in pressure.
I've thought about head gaskets, but that wouldn't really explain the coolant on the floor. I've though about an issue with the block, but that doesn't make sense when oil levels seems stable and the car runs like a dream. No oil on the floor. I do think it might be burning a little oil just from checking the oil level reading in the car, but it's always between full and half quart low and doesn't seem to change. I guess I'm assuming that at some point it was full and now it's down a little.
I know the front crossover has been replaced with an aluminum one somewhere along the way. I don't know what to do, but with the documented coolant system issues I'm not comfortable driving it much for fear of a major leak letting go and cooking the motor. I'm not the type of guy to fill it up, clean it up and sell it to leave the problem for someone else. I'm also more of a do it yourself guy but I'm not sure what to do.
Should I just replace everything from the head gaskets up and all the coolant lines and water pump? Maybe just the water pump, but I can't see any signs of that, but also can't rule it out I guess. Is there another test I could do to try and find the issue? I'm going to post this info on another forum too so if you use both sorry for the redundancy.
We really loved taking the LR to Cincinnati, it's great for our family, in great condition other than this weird issue, and we'd like to resolve this but I'm not sure what to do. Thoughts, opinions, and recommendations are welcome and would be very appreciated.
A couple background details. I'm not a mechanic, but I've been wrenching on cars since I was a kid. I'm almost finished with a complete restoration of a 70s Ford, I went to college for mechanical engineering, and I've done a lot of construction over the years including flipping some houses on the side doing most of the work myself. So, not a mechanic, but a pretty capable guy.
I recently purchased a 2016 Land Rover LR4. I wasn't looking for a LR specifically, but just a decent larger family car for an extra winter vehicle for cash mainly. I was told at the Used Car Dealer they had replaced the thermostat while it was in their possession. On the drive home I threw a CEL. It was lean bank 1 & 2, and Low thermostat temp readings. After some research I replaced the PCV valve and the little elbow thing in the cooling system with the upgraded brass one because I found it leaking. Cleared the codes, drove it. Threw a CEL, just one of the banks was lean and a low thermostat temp. Decided to change the thermostat. When changing the thermostat I found a vacuum line on the drivers side (US) underside of the air box was not connected. Replaced the thermostat, which I think was never actually replaced by the dealer, replaced the hose that has the plastic press fit deal on the bottom of the thermostat. Put the whole thing back together. Vacuum filled the coolant and put all the vacuum lines on. I drove it on and off for a couple days (maybe 40 miles total) with no issues, no CEL, runs amazing with everything working properly. Take a trip to Cincinnati, OH about 300 miles round trip. Runs great, no CEL, zero problems at all. Slight coolant smell when we arrived in Cincinnati, which I expected because all the coolant I was able to coat the engine with while chaining the thermostat. After the trip and the drive home barely any smell at all which made sense. The whole time I hadn't seen a drop of coolant, no issues at all. Park in the garage all is good. The next day I go out, coolant under the car. The coolant level was at the max cold fill level when I closed the hood after the work I did, it's just below the low level line now. So I top it off again and decide to drive it short distances for a few days to try and find the leak. several trips, no leaks, on the 5th or 6th trip park it in the garage and the next day coolant on the floor. I decided to pressure test the coolant system even though it held a vacuum when I filled it I figure pressure is different than a vacuum so we'll see where the leak is. I pressure test it for 25 minutes and not a drip of coolant anywhere no loss in pressure.
I've thought about head gaskets, but that wouldn't really explain the coolant on the floor. I've though about an issue with the block, but that doesn't make sense when oil levels seems stable and the car runs like a dream. No oil on the floor. I do think it might be burning a little oil just from checking the oil level reading in the car, but it's always between full and half quart low and doesn't seem to change. I guess I'm assuming that at some point it was full and now it's down a little.
I know the front crossover has been replaced with an aluminum one somewhere along the way. I don't know what to do, but with the documented coolant system issues I'm not comfortable driving it much for fear of a major leak letting go and cooking the motor. I'm not the type of guy to fill it up, clean it up and sell it to leave the problem for someone else. I'm also more of a do it yourself guy but I'm not sure what to do.
Should I just replace everything from the head gaskets up and all the coolant lines and water pump? Maybe just the water pump, but I can't see any signs of that, but also can't rule it out I guess. Is there another test I could do to try and find the issue? I'm going to post this info on another forum too so if you use both sorry for the redundancy.
We really loved taking the LR to Cincinnati, it's great for our family, in great condition other than this weird issue, and we'd like to resolve this but I'm not sure what to do. Thoughts, opinions, and recommendations are welcome and would be very appreciated.
