Skoda Rally Blog

After yesterday’s defeat, it was time to address the problem – I’d double-checked everything so I was sure the cam timing was right, the clearances all adjusted, everything else that could stop the engine wasn’t a problem, so the crank sensor must be the problem.  I got a timing light onto the car, and turned it over – and saw straight away what the laptop had said – the ignition timing was indeed all over the place.  The crank sensor was either faulty or just not in the right place – turned out that there was a but of rust on the end of the trigger, and it was also slightly in the wrong place, and the two meant that the ECU was getting a signal it just couldn’t deal with.  A couple of attempts saw it lined up perfectly, and suddenly a rock-solid ignition pulse showed on the front pulley with the timing light.

I reconnected the injectors, and….

… it still wouldn’t start!  It sounded more regular, but still didn’t want to go; it was willing but unable, basically.  I took the no.4 spark plug out to see what it looked like, and it had fuel on it, so that wasn’t the only issue.

But then as I was re-attaching the spark plug lead, I realised what had happened.  When I’d reconnected the leads, I’d swapped leads 3 & 4 over – on the old set of leads they were easy to spot, but now 3 & 4 are the same length, and I’d got them the wrong way round.  Hurried round, paused for a second (in a “I really hope this does the trick” way), and turned the key….

Instantly, it fired up!  Sounded good too.  Seemed lean, though, as it died quickly after (the ECU has a “priming” effect where it injects more fuel just as you turn it over to get it going), but that is good news – the new head and manifold should let more air in, so you would expect it to be lean at this point.  Fired it up again, and managed to keep it going this time – it sounded keen, and also mechanically good, so that’s a great start.  I can’t do any mapping until Wednesday as the car needs to be on the road for that, and it’s not taxed at the moment, so tomorrow will be spent checking everything over, and finishing off a few little bits here and there, but it is currently looking good.

Motor Excel - let's hope so!

Always good when a company puts their name on their product – but the proof of the pudding is in the eating.