Hi there, iv had a missfire on my sapphire for over a month now, the car is almost undrivable sometimes. The Wierd thing is i have changed all the usual things but its still there and still does the exact same thing, car cool, no problem goes like a bat out of hell, car warms up starst missfiring, gets worse more the car runs, hotter it get more the missfire, What could this be, sensor somewhere???? PLEASE PLEASE HELP!!!!!
Cheers
Lukeyp

 

act one m8 brown sensor on inlet ?

 

When it is HOT and idling do the wiggle test, I have seen a few that had problems with the CPS connector, not the CPS itself just the connector, as mine did, also make sure the gaps are correct PHASE 0.2-0.3mm, CPS 0.6-1.0mm, plugs 0.6mm, your coil could be on the way out as it does sound lecky in nature, but also could be amp, look at the wiring on the phase sensor see if it has disintergrated as they do!!.
Just a few ideas to keep,you busy
tabetha

 

will buy on 2moz and fit it, i'll let you know if it makes a difference.
cheers

 

Someone mentioned the air temp sensor, just spray liberally with CARB CLEANER to get the oil off this, but will not make much difference as MAIN CORRECTIVE factor(for CO) is temperature from CTS.
tabetha

 

whats the CTS Tabetha ?
thanks

 

Coolant Temperature Sensor, it is Ł10 or so, if the original one I would change it anyway, if you can get to a freindly MOT place and get the CO tested, should be 2 -2.5% CO at idle, to run nice, set this first.
tabetha

 

hi there iv changed both the brown sensor on inlet and coolent sensor but still no change, anymore ideas ?
thanks everyone?

 

i think it may be cps (crank position sensor) as mine is missing now and the rev gauge seems to be bouncing all over the place so im gonna start with that

 

as tabetha said have u checked your phase sensor??also r u running a group A coil ?

 

This could also be a loom problem. I had a similar issue with mine which turned out to be in the wiring to the Phase sensor. Like you, I'd replaced pretty much everything before this was discovered.

 

Had about the same sympoms last year. Could pinpoint the cause so a bought all of the sensors,plugs,leads etc. Turned out the phase sensor.
It had a badly corroded wire and when temps rose, the problems became worse.
good luck anyway.
(btw what's different with a gpa phase sensor?)

 

opps was ment to put group A coil

 

i had a misfire at 5000 rpm for about a year (no water loss or over heating either). i changed every single sensor with no luck. Turned out to be the head gasket.
Well frustrating after spending loads on leads, plugs, map sensor, coil, cap, water temp sensor, CPS, etc.

 

Hi mate how did you manage to find out it was the headgasket if it wans't losing water or overheating etc?

And why would the headgasket cause a missfire problem?

Thanks