Hello all, I have a 2011 Range Rover Sport HSE that I bought this past October...I had a LR3 about 10 years ago that I loved but wanted something a bit sportier... aaaand this Sport has been having some issues. Bought it from a dealership about 200mi away and it failed inspection immediately for some fairly minor things. Last month the rig died out of nowhere maybe 15 minutes from home after the dash began christmas-treeing...swapped out a new alternator and everything had been alright since. But two nights ago, at about -1 degree Celsius, I went out and started it to warm it up for a few minutes before I drove it. I started fine and idled for about 15 minutes, warmed right up, but when I got in and put it in Drive the engine/battery lights came on and it stalled. Tried starting it again a few times but it just wouldn't catch despite turning over. Battery tested at the terminals as 12.54V after that cranking. Belts looked fine, gas in tank, battery is from 6/22 and alternator is less than a month installed. Fuse F1 for the fuel pump is good, relay R8 I didn't test but appears clean and undamaged.
Next morning...went out and started it; it started after some longish cranking but died as soon as I revved it a couple of times while still in Park. Checked the battery itself and it tested out fine, charged it up a bit and then connected an OBDII. It threw a couple of ABS codes as well as an engine code P0420 that read on the ODBII as "Catalyst System Efficiency Below Threshold (Bank 1)" but when I paired the OBDII with its app on my phone the report came back "P0420 Blocked Idle Air Control Valve". I took the throttle body off (IAC valve is built into it and is not removable or user-end serviceable) the best I could and gave it a cleaning with some choke cleaner...but I couldn't get it all the way off as the 2 hoses on the bottom have bands instead of clamps and I didn't want to cut them as I had no hose clamps in that size and it was getting too dark and cold to be outside anyhow. Looking at one of the throttle bodies on eBay, it appears as if perhaps the IAC valve exit is about at 12 o'clock facing the intake manifold so I couldn't get at it. I'm going to get it all the way off early tomorrow and try and clean that valve's exit but I'm thinking...I'm probably stuck buying a new throttle body?

Or is something else perhaps the problem? What am I missing here?

Engine and battery lights are still on; it cranks but does not catch in the slightest.

I had the same code on my 2006 4.2 V8 turned out after doing live diagnostic test the MAF sensor was dud so changed it out
is yours petrol or diesel engine?

Petrol, sorry

thats ok
like said I had same code traced it to maf sensor

So, just a heads up - manifold absolute pressure, MAP; not to be confused with mass airflow, MAF. MAP has blown a code for me over the last four years quite often (P0106, seems like every other month) and then clears by itself. I’ve got the sensor in case drivability is affected (hasn’t been yet). MAP is a bit more challenging to access/ replace on my 2012 5.0 L petrol than the mass airflow MAF, which is very easy to replace. Best of luck and keep us posted. Vincit qui se vincit

Still trying to figure this out. Cranks but doesn't start.

Only a though, but do the NAS spec. cars have a inertia fuel shut off valve/switch that has tripped by any chance?

Cheers
Col

Very good thought there Col.