Loss of power and check engine light

Hello

Having some issues (again) with, ex-MOD, 2009 110 SW. On drive to UK, from south west france, the check engine light came on, but no obvious reason. Had someone plug in the diagnostic over xmas and the guy said it could be a butterfly valve that got stuck open that's now ok. He reset the light, and said to see how it goes, the light stayed off. The engine starts first time, but not so confidently lately, I thought it was the colder weather. On the return journey to france the check engine light came on , again no obvious problem, and we drove another 500 miles home with the light on. Now, a couple of days later, I'm losing power for the first few minutes or so after a cold start - put my foot down and nothing happens, have to keep the revs up ...

Maybe the power loss and the engine light are unrelated. Any opinions gratefully received!

Cheers

wot injun?

There are literally dozens of possible causes. You will need to get a diagnostics tool compatible with the Land Rover's ECU (such as Nanocom) which will tell you directly what the fault is or give a fault code which you can check on the lists in the official workshop manual. Cheap cd versions of the manual can be found on eBay for a £few but a nanocom is not cheap (several 100 £) but will pay for itself over time.
I've no idea what your mechanic means by a butterfly valve. If you have a fault code I can look it up for you.

OK, thanks, I've got a manual, but not the code - I'll email the guy and ask if he remembers ...

Wimblowdriver said:

what your mechanic means by a butterfly valve.

Click to expand...

Wonder if he meant EGR valve?

Yes, you're right, the two faults were the air flow meter and the EGR valve. Apparently, each of these faults can set off the other. Anyone know whether one, or both, could be cauing the power loss and stalling after cold starts? Cheers.

If the air flow meter is duff the ECU will not know how much fuel to inject (your injectors are electronically controlled by the ECU). So the car will go into limp mode to prevent serious engine damage.

For your homework tonight, read the manual chapters on engine controls and emissions controls

Two things to try, first unplug the mass airflow meter and see if it runs any better, if so you can try cleaning the sensor with a special MAF cleaning spray to see if it works ok after cleaning, if not replace it, and remove your EGR valve and clean it and the pipe and inlet manifold.

Wimblowdriver, yes, I've been reading the manual. As a complete beginner, I always find reading the manual very distressing! I'm desperate to avoid (another) painful bill though ...

Thanks Scooby, I'm going to try and pluck up the courage to get under the bonnet (if that's where these things are) and follow your suggestion. So the MAF, is it a sensor of sorts?

I'm not sure that disconnecting the MAF will do anything or improve running. It might on some engines but not on a tdci as the ECU will still not know how much air it is getting and will not know how much fuel to inject. Changing the MAF (sensor) is a simple unplug old one, plug new one in, I will dig out the workshop sheet in a little while and attach it to this fred. First try cleaning it, if no improvement replace with a genuine item.

Hope this helps. But bear in mind the fault might be elsewhere.

Its an easy no cost check and it has been a well documented check on the TD5 model with ecu so nothing to lose by trying it on TDCI.

Thanks again for suggestions. My MAF cleaner arrived a few days ago, and I cleaned it. I'm not sure whether its helped or not yet, as the problem occured in sub-zero cold starts and its been warmer lately ... In the mean time, the check engine light comes and goes!