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Discussion Starter #1
this is new... I was driving home from work the other day and it was our first rain of the year. About 5 min into a normal drive nothing hot roddy, the engine starts making a nasty shudder that I originally thought was the tranny but I put it in neutral and it still did it. The entire car shudders while driving and shakes like its going to fall apart. almotst like theres something wrapped around the driveline and its beating up the underside. Now imagine how my rear end puckered while this happened... in the rain... a half hour from home. It took me about an hour to drive home extremely slowly and the whole night I wondered what I was going to do and how I was going to fix it or more importantly WHAT THE HELL WAS IT. but then the next morning I fired it up and it started no problem. Like a top. I babied it for the next week just incase it wasnt a fluke and then yesterday I took it through the auto car wash which has an undercarriage wash. About 10 seconds after the undercarriage was hit it did it again. I immediately shut the car off and let the wash finish. started it up and it ran like crap, then shut it off and then back on and BAM.. like new again... PLEASE HELP..... what is it... Im getting into the rain season and this is really gonna suck... Im thinking a engine management harness is shorting in the water. !!!
 

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Hello,

Last time I had something like this, it turned out to be cracking plug wires (on an Ford Ranger). It was during a heavy fog/mist. To troubleshoot, the next time it was very damp, I went out while dark and lifted the hood a little and peaked under. It was like a mini light show around the plug wires. This is a fast and easy check. New wires solved the problem. This is my 2 cents worth though.

Good Luck!

Bono
 

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Freude am Fahren
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I'm in agreement with JBono; it's probably something to do with your ignition system.

Check for water under the passenger side cabin air filter compartment***8212;the engine computer is there.
 

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Yeap,

Ignition System:
- Check Spark Plugs age/mileage
- Check Ignition Coil Rubber Boot (Ruuber Boot can crack). They are inexpensive and easy to replace.
 

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What you can do, take a canister (something like a water container with a spray nozzle for spraying plants) make sure it can produce a nice mist of water.
Let your engine run idle, open the bonnet and spray some water mist above the engine bay. You should see little sparks emitting from the ignition wires.
In the dark the effect is better visible. If this occurs its a sign that the ignition wires lost their isolation properties. The rubber based isolation deteriorates over time due to the
heat cycles of the engine and bad 'environmental' conditions in the engine bay.
 

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There are no "ignition wires" on these cars: it's coil-on-plug.

Do you, by chance, have a cold air intake on this car? If so, you may have sucked in some water. Best to remove it before you suck in a bunch of water and trash the engine.

Otherwise, there may be a connector under the car that is getting wet.

Are the underspray nozzles at the car wash relatively high pressure? If so, avoid them. They can force water into connectors and cause corrosion.

That also goes for high-preesure engine washing: don't do it.
 

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Discussion Starter #8
will check plug wires... will report back asap.. thanks guys. but if it is the case... why no engine light... a misfire causes a light right?
 
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