Let me give you a quick bit of background....
A few weeks back my car started misfiring on cylinder 5(Checked fault code). It was misfiring quite badly whenever I gave it any sort of beans at all. Thing is, it could seem fine one minute, then I press the go pedal a bit much and it misfires badly (Engine light etc... juddering) and it would keep doing that until I turn off and on. After that its fine again. So its not a constant misfire like id expect from a mechanical problem.
2 weeks later I had my mechanic put a set of NGK Iridium plugs in for me, gapped at .8. He also swapped coils 5 and 6 around so that if the coil was faulty, I would get a fault code for cylinder 6 if it was still misfiring.
After the work, the car is still misfiring but not as much, only under high rev's and if I give it a lot of welly. Infact, it almost seems random as I have booted it all the way upto 130 and it still didnt misfire to the extent it was before the plug change.
What I also notice however is a fair loss of power (Which i beleive is a typical symptom of a misfiring car).
But the plot thickens....
Last week I started the car up in the morning and noticed a low coolant warning light. This light went away when I turned the car off and back on. But then I started the car again after work and it was back.
I checked the water and sure enough the expansion tank was empty and the car drank a good litre or 2 before it came back up into the expansion tank. I havn't seen any drips from under the car.
Now that was Thursday. I got up for work this morning and got in the car, coolant light is on again and sure enough i needed to put more water in the system. About a litre I would say.
I have a new coil ready which is going in tomorrow when my mechanic looks at it.
The question I have is, the coolant loss has only started happening since the new plugs went in and the coil was swapped around. So does this sound like a case of something not back on right, therefore causing a leak?
The fact that the car isnt misfiring enough to get me a warning light and error code makes me think its a dodgy electrical part (I.E. Coil pack). Sound about right?
Any input would be greatly appreciated!