Need help with unusual electrical gremlin
 

Here is the history:

Took car to car wash last week. I never go to these, but it was the touchless style. The car was running, and when the machine sprayed in the front of the car, it stalled. I have a Roush bumper, and it is a lot more prone to water getting in. BTW, my low coolant light came on too. It ALWAYS does this after washing under the hood, but I did not do this on this ocassion. I have always suspected a wierd electrical problem associated with water and the coolant light.

I had a hell of a time getting it to start and when it did, it ran like crap. I suspected wet coils. After opening the hood, water did not appear to get into the plug areas at all, just down in the lower area.

After letting it dry for 3 hours with the hood open, I could drive the car, but the idle was horrible. It would want to idle at 3,000 rpms. If I unplugged the TPS, it would make no difference at all. So, I figured the TPS got shot and it was a coincidence.

I replaced the TPS and car ran fine all week.

Saturday night, I wash the car in the driveway with the hose. I don't recall if I ran it after that. Wife takes the car this morning and comes in the house saying that the coolant light was on. I told her not to worry about it and told her just to drive it.

On the way home, car starts to idle again at 3,000 rpms.

After she gets home, it sits for a while. I take it out three different times and it ran perfectly.

What the heck is going on here? There seems to be a connection between water, the coolant light, and bad idle. Does anyone have any ideas?

The coolant light runs off of a sensor that is actually in the coolant over flow. If you look just above the lower radiator hose (the one that goes from the coolant tank to the bottom of the block) there is a plug for that sensor. It dosen't do anything but tell the low coolant light to come on when the float get's too low. I really can't see how that would cause any idle issues. Due to my Canton expansion tank, mine is totally unplugged and my light is off, so I know it will work with that completely bypassed.
If the car keeps burning up TPS's there must a short in that circuit somewhere. See if you can get a wiring schematic from Randy Stinchcomb or someone that has access to such things and see if maybe the Coolant Level Sensor and the TPS circuits are in the same loom. Maybe you have a couple of crimped wires and they are shorting at the same time. Also check and see if the MAF or IAC are in the same loom as the Coolant Level Sensor. If the wires are shaved down or crimped enough to show a little bare wire, maybe the water is just enough to complete the short and make the system go haywire until it drys out.
Are you getting a Check Engine Light? If so, scan for codes and see what you come up with.

I have a Haines manual. I'll start from there.

Thanks for the ideas.

I don't know if a Haines book will have that but it's worth a shot. Maybe try running the car and aiming a hose at different parts of the engine. Try to centralize the stream of water so that you can narrow down exactly where your problem is coming from. If you find that spraying the water at a specific area causes the problem, it may be easier to find the exact problem.

Now to add to my woes, the security light started flashing tonight while driving the car. I think that happened because of a glitch with my SCT chip though. I was parked in a shady area, so I set my chip so the car could not be started. Wife went to the car and tried to start it. So, I put the switch in the correct position, started right up, but had a flashing security light. After driving a few miles, I shut her down and restarted the car. Light went away.

I think that's just a coinkydink. My Security light flashes all the time.