Service Engine Soon When Car Is Wet

When I get a carwash or after a big rain, it seems like my service engine soon light is prone to coming on. The problem is that although it doesn't stay on for more than a couple days, it prevents me from getting gas because the valve disengages and the pump will only put a couple dollars worth of gas in before stopping.

I had it checked out and the mechanic said it looks like water gets in some reservoir or something but it's okay?

BryanR, Don't take offense , but it's time for a new mechanic. This sounds quite unusual, correct me if I'm wrong, you're saying that when the check engine light comes on you can't get gas because the gas pump keeps shutting off? I have never heard of anything like this, HAS ANY ONE ELSE?

There shouldn't be anything preventing you from getting gas let alone a mechanic saying it's OK. Is there anything else going one when this happens? Like poor running, poor idle, other lights on? This just doesn't make sense, something is not right.

Stay with this the guys/gals on this forum will come up with something.

Hoags is right, there is nothing that the CEL or computer controls that should prevent you from putting gas in the car. This problem sounds to me like you have a sensor that is getting wet and causing the CEL to light. It is not normal for this to happen. Possibly the weather pack connector to the crank position sensor is going bad. I only say this because I am trying to think of a sensor that would get wet in the event of a rain storm. The only other possibility is that the PCM is getting water in one of the connectors but I would think that the car would run poorly in addition to the CEL. As Hoags says find a new mechanic who is willing to take the time to track this one down.

Next day and still on. I woulda thought it would have dried out by now!

Car runs fine, just that stupid light is on.

Have it scanned at autozone to see if maybe something malfunctioned. If so the scan will help you determine what may be wrong.