No start when air is high in moisture

[twinturbo2.9]

My 1992 ford ranger with the 2.9 v6 will not start when there is alot of moisture in the air such as a foggy, drizzly or rainy day. It will crank over but will not start. If there is not alot moisture in the air like on a cold day It will fire right up. I think it is possibly the distributor cap. Has Brand new plugs 2 weeks ago. any help would be appreciated.

 

[Tedybear]

This test is best done in the dark...or low light level.

Use a garden spray washer type bottle. Start the truck (or try to) and systimatically (you get the idea...so I cant speal). Get a light mist over select parts...you'll be looking for any bright flashes, and listening for any 'snap' type sounds. Both will point you in the direction of the problem. The flash and/or 'snap' sound would point towards electrical arcing. Also if you mist over a certain area, the the idle goes turns to crap? You'll want to check that area for wiring issues.

If it's been a while? Cap and Rotor replacement, along with new wires wouldn't hurt. Caps love to develop what is known as "Carbon Tracking". If it's just starting to do this? The increased humidity will trigger it faster then on a dry day.

S-

 

[twinturbo2.9]

can you remove the rotor without pulling the distributor. If you can how do you do it.

 

[IMenriched]

can you remove the rotor without pulling the distributor. If you can how do you do it.

Yes it clears...once loose ya might have to roll it off one side or the other, where there is more room to bring it up.

aggreed that finishing the tune up is best.