I believe my mate said they are not 100% accurate at determining exactly which cylinder is misfiring.

 

As you say don't take it as fact - don't!!

My light came on way before there were any other noticable signs for me.

When it came on I was in France, so didn't have much choice but kept an eye on everything, temperature, oil level etc.. just to be extra carefull.

As I said, it was ages before anything was noticable.

 

Aj - it'a calculation using the crank sensor so it can be hit and miss. It is normally quite good at spotting one though.

 

yeah it'll be crank sensor and rpm so it'll be difference in rpm on cylinder.

There was something on the same lines on plant (at work) a month or so back, but that was using PLC watchdogs.

 

Same thing really, just gets more complex on industrial recip engines with 12 cylinders and 4 turbos!

 

I sent my four injectors away to be cleaned. The turn around as very quick and they did find that one of them was gummed up. The car has been running better since then.

Odd that you don't have a CEL

 

Fair enough, but my experience of two injector caused misfires on two engines was the opposite. Even with it misfiring quite badly, there was no CEL.

 

It was better today, didn't misfire as much & still no CEL. I'll keep an eye on it.

 

I had a look at the plugs today. All were ok with the correct gaps, except no. 4 was slightly small.

I then looked at the throttle body which was quite messy (10 years of gunge).





So I set about giving it a good clean & used the air line to make sure the passage to the MAP sensor was clear.





I also cleaned & re-oiled the K&N.

I started it up & it wasn't misfiring so much, but I really need to take it on a run to assess it properly. I may have a go at cleaning the injectors as well, if it's not too difficult.

 

Nice pics, you didnt have to take the TB off

Good job, did you spray towards the back of the intake manifold? - that will get caked up too.

I clean mine about once a year.