Problem with missfire and codes 17 + 23

[uk_mx3_guy]

Hi,

I have a problem with my KL-ZE.. It has recently developed quite a bad missfire from a cold start, once the engine gets up to temperature the missfire seems to go away!

The car also trys to stall when I stop, the revs drop and will either go back to normal or will actually stall.

I have changed both O2 sensors, fitted new spark plugs, new HT Leads, replaced the disty cap and even replaced the IM gaskets... however none of this seems to have made a difference

This morning I cleared the ECU codes, run the car and got new codes - 17 and 23

Does anyone have any idea what might be causing all this?

Im running out of ideas now

Thanks

Jono

1994 (UK MX-3) KLZE (Jspec)

[Kirk95gs]

Thoughs codes are o2 codes are they not? Have you changed your catalytic converter befor? could be old/pluged up causing wrong readings in the o2's. It would also cause the hesitation and idle issues.