Rover 100 starting problems

[technophobe]

Has anyone experienced a rover 114 sli not starting when its out in the rain? In the dry it fires first time & runs smooth, but inthe wet it will not fire, i have checked the ht side and sparks are available, also the fuel pump runs to build up pressure for fuel rail, but it will not fire when wet, it turns over ok i've even almost flattened the battery trying to start it in the rain, but go out the next day when its dry & it fires up no probs, i;ve even moved the fuel pump relay box away from its position under the inlet for the heater but to no avail, any ideas anyone???

[chevrolet1.8]

unusual for modern cars to experience this but on older cars damp problems were more common. try spraying the leads with wd forty or any other moisture repellent when it's dry and running ok and see if it's any better after that.