I have a 2002 subaru forester. My question is that when weather is nice and beautiful my car runs great. But when it’s damp or raining outside it won’t start at all. It cranks but engine won’t start. I used a scanner to see what was wrong but scanner shows nothing. I know it’s an electrical problem but don’t know from where and im depress because of this because this is my 1st time buying or even having a car. Please help. Also could it be the fuel pump or need new spark wires? Thanks hope to hear back
No need to be depressed. It is problem to be fixed, not a life-long condition!
So the scanner shows nothing when the car runs?? No codes?
I’d suggest this is an electrical problem based on the symptoms and the car’s age. Look for ground straps and wires (usually black) screwed or bolted to the metal parts on the car. Are they showing white crust or red rust? Unbolt, clean with a wire brush or sandpaper and re-attach.
Check the condition of your spark plug wires. If they’ve never been replaced, it is probably time.
Both those should move you forward to a solution. Post back with what you find and we’ll keep trying to help.
The first thing to check when having this kind of issue is the ignition system. Make sure power is getting to it and that spark is getting to the plugs. Also check for any arcing to ground from the plug wires while the problem is happening. If you can catch the trouble happening during the evening look at the plug wires while it is dark out to see if you can spot any arcing to ground.
The first thing to try is replacing the spark plug wires and the spark plug tube seals.
If that doesn’t fix the no-start condition, then you may be looking at a bad ignition coil.
Tester
2 Likes
The relationship to damp weather is a big clue this is related to the high voltage part of your car’s electrical system. that means the ignition module, spark plugs, spark plug wires, and coils. This should be very easy for a shop to diagnose. They’ll use a spray bottle filled with water and spray a fine mist of water on those parts to see if they can get it to show the symptoms. Replacing the spark plug wires proactively makes sense too, as it could very well solve it.
I had a VW Rabbit one time that would stall out every time I drove over a puddle of water. I had to remove the coil and inspect it on the bench using a magnifying glass to figure it out: a tiny crack in the coil housing. New coil, never happened again. Electricity at high voltages doesn’t obey the normal “follow the wire” method. It jumps through the air at every opportunity. Best of luck.
1 Like
Wires are welded to plug tube seals on this engine, it is one set
The first Subaru I used to own was 1998 Legacy with 115K miles on it when I bough it.
I experienced the very same “sensitive to wet weather” symptoms right after purchase and a set of new high-voltage wires cured it immediately.
https://www.rockauto.com/en/catalog/subaru,2002,forester,2.5l+h4,1378739,ignition,spark+plug+wire+set,7224
https://www.rockauto.com/en/catalog/subaru,2002,forester,2.5l+h4,1378739,ignition,spark+plug+tube+seal,7220
Tester
wow!
factory-original DENSOs are only $25, great-looking and the same guaranteed-to-perform-nicely NGKs are $30
not bad 
at that price, I would not go for cheaper ones