It did not run first time...

Kathryn eagerly filled up the tank with a bit of fuel and we made a number of pre flight checks. All looked well and even the battery (that's been sat for about 12 months) appears to be fully charged. 

The anticipation was unbearable as we went for the first turn of the key. The familiar sound of an engine turning over on the starter motor and then seconds later a string of backfires.

Again a few minutes later- a string of backfires.

Another few minutes later and Matt suddenly noticed one of the coil packs smoking and melting before our eyes! Oh dear...

Bang Bang Pop

A quick video to help you diagnose what's occurring when your coil packs are wired the wrong way round!

So a thorough investigation was launched (just minutes after buying a new set of coil packs on EBay). 

Problem number 1. We had got the signal and live pins mixed up on the melted coil pack. It probably melted because it didn't enjoy 12v where it was getting 12v.

Problem number 2. The GBS loom appeared to have the coil packs wired the wrong way round - at least that was a quick fix, just meant rearranging the pins in the Deutsch connector to make pack 1 pack 1 and pack 2 pack 2!

Once we were finally up and running, the time had come to calibrate the throttle position sensor (otherwise it runs like a dog) and balance the throttle bodies.

The Emerald software makes calibrating the TPS really easy. 1.Plug the ECU in to a laptop running the Emerald K3 software. 2. Open the TPS calibration wizard. 3. Follow the instructions and save the map!

Balancing the throttle bodies was a bit trickier. A bit of faffing about trying to find the 'highest low' airflow setting of all the bodies and then bringing the other 3 down to match that one. The MX5 manual suggested we should be running 950-1050 RPM at idle, so Matt plumped for 1000RPM and adjusted the end stop for the 4 accordingly. 

Seems to run pretty nicely now after re-calibrating the TPS. We are running on a map stolen from Kevin Broomhead who is running the similar setup as us. We will have to see how we get on with emissions at the IVA and potentially go and book a rolling road session afterwards to release the little engine's full potential!