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Adventures of a Traveller

'Moose'

ECU's Me Sir!
21 January 1999

We've struck a problem. Maybe.

I've been hearing rumours that the K-Series electronic control unit (ECU) has problems coping with running at high altitude. Apparently a number of MG-Fs that had been exported to the Johannesburg in South Africa have all suffered burned out pistons. The cause of this appears to be due to the lower atmospheric pressure at high altitude and therefore less air getting into the engine. This means that less fuel is required and so the engine's ECU makes it run leaner. The only trouble is that it appears that the standard UK-spec Rover ECU overcompensates and causes the engine to run hotter than normal and burns out the pistons. That's the theory anyway.

So is there really a problem? And what's the answer if there is?

Well, I've contacted Rover/MG and they deny all knowledge of a problem (which they would anyway). I've also contacted K-Series experts Caterham Cars. They did admit to a drop in power on their high performance engine but nothing as serious as burned out pistons. Other K-Series tuning shops have said much the same. We're not going to South Africa anytime soon, but we will probably be doing some Alpine work in Switzerland and maybe even the American Rockies (if we're lucky). So should we be cautious and swap the ECU for a modified one that has an atmospheric pressure sensor and a multi-mapped ECU? Or since we're changing it anyway, should we go for a performance version coupled with larger throttle bodies that gives 160bhp and is fully programmable by me using my laptop? Either way it's going to be expensive - we're talking over £1000 for the basic modified ECU and more like £2000 for the throttle bodied performance setup.

Another option is to ditch the ECU all together and run a pair of 45mm Weber carburettors. This will eliminate the ECU problem but it would mean that we couldn't run a catalytic converter, something which I'm sure we will need when trying to register the car back in New Zealand (the modified vehicle laws in NZ are getting stricter by the day). Or we could do nothing and hope for the best. Decisions, decisions.

Apart from that though, work on the car is progressing well. The engine has been trial fitted to ensure that all will fit in the engine bay nicely and that the engine mounts are in the right place and that the gearbox will line up with the axle correctly. Jonathon has filled all unnecessary holes in the engine bay and has seam welded/filled all joints for a smooth look. A bit of extra strengthening, just in case, has gone on the chassis rails in the form of 3mm plate gussets and plates. It's nearly ready to have the engine bay and interior painted so that the engine can finally be fitted and wired for noise. The next few weeks should see Moose beginning to look like a real car again.