I’m having a lot of issues with a ‘09 Clubman S. After it’s ran for about 20 minutes and it’s warmed up it will stall out and not restart. Will a coolant temp sensor cause that because that came up on the scanner along with both front and rear 02 sensors. It sounds like it wants to start but doesn’t. It does have low compression as well. 70,70,70,95 .Only 54k miles

 

If you are getting codes, check them out. Logically, if it stalls after warmed up, something with the temp is up. So, change the thermostat, check coolant, etc. However, if compression is an issue, get the engine checked.

Kat

 

Low compression sounds like timing chain or dirty intake valves. In addition could be fuel issue. May be pump.

 

Is the car running basically OK before it stalls out?
I am suspicious of those compression readings. Was the test done with the plugs out & the throttle wide open?
Does it start OK once it's cooled a little?
It sounds like an overheating issue. What are the codes?

 

Bought the car at Copart and said “mechanical issues” when I got it home the coils were pulled and valve cover was loose and the bolts in passenger seat. Put everything back together and started it, sounded like a fluttering knocking noise not a rod knock but different. I sucked some Seafoam into the intake and made a world of difference. Sound and running wise.

i did the compression check with the plugs out dry first then wet. After adding a oz of oil all cylinders came up about 30 lbs. Then I did a leak down test and showed zero pounds but didn’t realize you have to do it at TDC so I will do that again.

When I start it cold it starts about 3 seconds and runs and sounds great however if I let it idle it will die so if I keep it about idle until it warms up then let of it will die and not restart. I don’t remember the code #s but showed both 02 sensor plausibility along with temp sensor and cam sensor. Also have a “unmetered air” code.

When the valve cover was off I couldn’t believe how dirty the head was looked like a lot of carbon. Changed the oil and was very thick and black! I’m hoping the rings are not bad just maybe head work from carbon build.

 

Quite frankly, Alconk, this might be a bit beyond where an on-line forum can help. It does, however, sound as though you know what you're doing, which is helpful.
My own guess is valve timing, jumped chain or cam issues - but that's a guess.
Hopefully, someone will have seen similar symptoms to your good description & can join in.

 

Well I think I might have going the problem, I put the engine in timing mode and found it to be two teeth on the chain so from what I read the tensioner can fail causing the chain to stretch thus the jumped teeth. I don’t know what causes this especially at 54k miles?

 

That seems quite likely to me. A weak or failed tensioner is a common problem, though the mileage is low.
It's not an expensive fix, which is nice!.