Buddy of mine has a Glanza V. Over the last week I fixed a few things on it, one of them was a broken temperature gauge, and the other was fix the high idle. The car was idling at 1,300-1,500 rpm and I dropped it down to where it should be, 800-1000 rpm. Everything was ok but when the car was started up from cold it would misfire for around 10-15 seconds then be perfect, only happened after I fixed the idle, it got progressively worse over the passed few days. Today the plugs were changed and it is still getting progressively worse, it only happens off throttle or when the car is idling, as soon as the accelerator is pressed there's nothing, a while ago it just started to misfire up the revs in 2nd and 3rd gear when driven hard. After fixing the temperature gauge, around three days later we were parked outside the shop and the temperature gauge rose up and nearly went to the red, we knocked the car off and waited til it went cold. I first taught it was an air lock so I bled the cooling system and that sorted that out. Today the car over heated again. The car has not boiled over to the red and has not boiled through the expansion tank. Just went up to just under the red on the gauge. The car only over heats in traffic and as soon as the car is driven it will go down to normal operating temperature again. Any idea what this could be? There's an aluminium half-rad on the car with 1.1 bar rad cap. The fan is working as it should. There's 4 magnecore plug leads and one standard king lead but they're very old. Car is boosting .5 on a CT9 with a fmic. NGK heat range 7 iridium tipped spark plugs. No coolant in the car only tap water but it's only in around 3 weeks with the new half-rad.