Hi All. After over a year of trouble fee and thoroughly enjoyable motoring, my beloved XK-R (2012 facelift 5.0 supercharged) has thrown me an engine warning light. Scanning it with my iCar Soft gizmo, I get the error as: P01010B-00 - Mass or volume air flow B circuit - range/performance. The car hasn't been used much over the winter months and though driving fine, I've noticed once or twice a very slight hiccough on acceleration. It's almost unnoticeable as a slight miss-fire, my first reaction was that I'd spun the wheels on some wet or greasy road.

Scanning the forums, it would appear the culprit is an air flow meter censor (aren't they all!?), of which there are two located behind the inner front wheel arches. Does anyone have any experience of replacing or cleaning these? If so, any hints or tips would be very gratefully received.

 

I would approach it patiently because it is the winter months of under use. Ask yourself if the throttle body has been washed in the last 2 years? Are the plugs top of the line platinum coated and rated for 160,000 kms? Your gas could be stale and don't tell me there is ethanol in it!

 

It’s highly unlikely the MAF sensors are dirty, over 2 decades working on cars I’ve yet to see any or have any faulty MAFs. The X150 filter housings are quite well sealed. How many miles since the last filter change?

 

I've seen a couple bad sensors, but it isn't very often. People tend to change them first as a matter of course. There could possibly be a problem with the connector or wiring though. Not saying the MAF IS okay, but there are other things to look at also.

 

Thanks for all the input - very much appreciated and I will do some further investigations. The car has done around 85k miles and had a 10k service last year - not sure if the air filters would have been changed then to be honest? I'm guessing the throttle body hasn't been touched, so will look into that. It's been ran on nothing but premium since I've owned it (coming into 3 years), so I'd hope it isn't bad fuel.

Again, thanks foer the advice and input - it's what makes keeping these monsters on the road passible for "normal" people!

 

Just a follow up Deugar, my suggestion was to wash the valve inside the throttle body. If they get dirty, it changes the idle air/gas ratio. When fuel sits, the ethanol separates from the gasoline and leaves you with a very low octane gasoline, on the bottom, near the gas line. And that is what you would be using!

 

So, thanks to all the input I checked my last service and as it looked like they'd replaced the particle filter under the bonnet but not the two ntake filters under the wings, I ordered the filters and set about replacing them over the weekend. I also decided to clear out the throttle body with MAF spray. All went fine until the second air filter when the cassette was a little tight. When it eventually slid away, I was confronted by this!:


After a thorough clean with Bunny-B-Gone! all back together and she's running a dream. Raises a couple of questions - how the hell did it get in there & considering it's been in there considerably longer than I've had an engine warning light, how didn't it get picked up sooner?

Anyway, thanks again for the advice. You were right, it certainly wasn't the MAF sensors!

Oh, and you don't need to remove the full bottom plastic tray as I did. You can replace the air filters by just removing a few screws from the under wing wheel arches.

 

yeah…. decaying bunny clogged the filter. Never seen that before.

 

Wow! Guess the blower has good sucking power, picks up more than just dust bunnies! Keeping the highways clean for everyone!