Why do Fords runs so bad in the rain?

I am willing to bet Steve has the answer. I had a 72 Dodge pickup years ago that did just that. It didn't have to be below freezing to ice up either. It would happen sometimes with temps in the 40s on foggy, rainy or otherwise moist days. The truck would start up okay and after a bit the idle would get slower and ragged and eventually it would stall. Once enough heat built up to melt the ice, things were good.

My '74 Comet I had in high school had a similar problem..the heat pipe going to the choke was rusted apart. Once I replaced it the choke would open normally and it quit stalling...I guess electric chokes take care of that problem

I would check to make sure your heat riser tube to the air cleaner is connected....

 

A lot of Fords are real marginal on the alternators and barely adequate when brand new. Get your alternator tested or upgrade to a higher amp. Defrost blower fan on high, headlights, wipers, low idle speed really pushes a 60 amp alternator. Even my '88 Mustang idles really low (like less than 500 rpm) at stop lights with everything running full blast.

Cleaver

 

Basically, the idle speed slows way down on a rainy, humid day. Other than that, it runs fine...

 

That is pretty much what it does.I have put a new stove pipe on,full tune up etc,etc..But it will do it in the middle of summer only when it rains.It's a 1979 f150 460,it has a holley but i have tried an edelbrock and a autolite also with the same resaults.Maybee i'll try and build a air cleaner with dual inlets and stove pipes Derek.

 

My '69.5 ran great for over 260 miles today, pouring rain most of the way. Everything from running 75 mph down the interstate to sitting in stop and go traffic on I-85 in rain so hard that the windsheild wipers could hardly keep up on high, with the defroster, lights, stereo and everything going full blast.

If anything, it seems like my Fords run better in the rain... LOL

 

Engines will run better in the rain!

They use to sell a Holley kit that injected a fine spray of water into carb. It worked off of vaccum when eng was under a load. Winter time you would run windshield washer fluid. Claimed more power an better fuel mileage!

I've never had a problem related to just Fords running bad in rain, unless it was with dist. cap moisture (would spray wd-40 in cap) or bad spark wires grounding out.

 

Heck it doesn't even have to be raining just damp like after it has rained,and my 79 is not the only vehicle that does it my wifes 84 crown vic 302 2bbl does it too.The funny thing is that it will run crappy unless you shut it off and let it sit for 10 min,then restart it and it will act like it was flooded,then it will run fine.Both car and truck will act the same way.Derek.

 

Carburetor icing will make a car run badly but after twenty minutes it should clear up and run right - unless you don't have the warm air feed to the intake or the cross-over heater is not working. If you have blocked off the cross-over in the intake manifold or are running an Air gap intake then you are living with the problem that you created by using racing concepts on the street.
The Ignition should not be getting wet unless you have modified the airflow under the hood to bring water up and in front of the engine. If you have carbon tracks on the coil nipple or in the distributor cap then slight moisture MIGHT affect it but I would expect any high output ignition would show it up as a problem whenever it was running.

 

None of my Mavericks have had a problem running poorly when it rains, but all of my 6 cylinder Mustangs did. The problem was moisture getting under the distributor cap. Once the inside of the cap was dried out, the cars ran just fine. I fixed that problem by doing what dkstuck suggested and spraying a light coat of WD-40 under the cap. Problem solved. What I never figured out was why this moisture problem only seemed to affect my 6 cylinder Mustangs and not my V8 powered Mach 1.

 

mine does exactly the same when it is damp, runs perfect in freezing weather if it is dry. runs great in wet till you stop then have to put it out of gear and give it more gas till light turns green, sometimes will even die when you let off of gas to put it back in gear.

 

My 'ol man showed me a trick when I had my first maverick (first car) in 1986: spray a rag with WD-40 (don't have to drown it) and wipe out the inside of the dist cap. The WD-40 will not allow the moisture to condense on the walls of the cap and therefore it can't misfire and give you the wet weather problems. Worked like a charm.

 

Derek, I can see that the only logical solution to your dilemna is to sell me the whole miserable fleet for a song and be done with them. Get a new Hyundai and be content with mediocrity!!

 

I had this problem on my 2.0 in my ranger and what I did was the dis. sits at an angle and at the bottom of the cap I drilled a .030 hole through the cap and that got rid of my problem. But everytime it would rain for some reason I would end up with moisture in the cap, but after I drilled the hole I no longer had the problem with the moisture under there.

 

Sounds like the general consensus is moisture in the distributor cap....

 

Tip......


If it is moisture. Wait unil a dry sunny day. Take a spray bottle filled with water and spray the igntion system. Start with the cap first,then hit the wires. If it stalls right away you found your problem.