Bear with me on this guys, theres a wee story involved !
Was washing down the truck last weekend when my young nephew appeared and wanted to give me a hand. I did the roof and the hi bits and then left him too it, big bucket os soapy suds and the garden hose.
Went out 15 minutes later and he told me he even washed the engine !!!

Yup, garden hose straight over the engine, everything soaking !!

Left it to dry for an hour, started it up, drove about 5 miles and everything was running great. I was worried about the Electrical side obviously.

Went to drive to work yesterday morning and its running real rough !
Showing code P0300= Multiple Cylinder Misfire.
Engine light flashing and then staying on.
So far, I have removed all the coil pack plugs, blew them out clean and dry, also done the same with the Camshaft Sensor, Crankshaft Sensor, Fuse box, ECT sensor, IAT sensor, MAP sensor in fact, every plug and connector under the hood has been thoroughly dries and sprayed with an electrical cleaner.
Started first time, still rough, but not as bad. Sounds like an old small block with a couple of ignition leads missing ?
Cleared after about 4 miles and ran perfect. Took it about 20 miles or so and never missed a beat.
Went this morning, still running rough, clears up when its warm and no codes this time ?? Have I missed anything, or is there something else I can try ?
Could it have fried a sensor ? Definately no water in or around the engine.
Apoligies for the novel, and all help gratefully appreciated.
Ooops, should add, its a 2003, Ram 1500 pick up, Quad cab, 4.7 Magnum.
We are a wee bit short on main dealers across the pond over here in Scotland !!

Thanks in advance, Alan..............

 

P0300 indicates to me that you have a wiring issue with the coils or the packs themselves aren't working right. Have you pulled the coils and spark plugs to see which ones aren't firing properly? (you can see it when you pull them. lol)

 

Yes you need to try and narrow it down, you will need to read the "pending code" not the "stored codes", which means you need to get your hands on a scanner... that will tell you which ones are misfiring intermittently.

Sounds like you may have a bad coil...

A side note: I'm surprised a young kid could even get the hood open all by himself...

 

Not yet, assumed as it had been running fine before the soaking, the water wouldnt have done any lasting harm ?
New set of plugs due anyways, so maybe kill two jobs with the same action.

Thanks mate !

Alan........

 

Yeah try new plugs (COPPER CORE ONLY!) and see where you end up.

Let us know if it doesn't fix the problem.

 

Getting hold of a scanner over here that does these vehicles will be tough, but will start the ball rolling tomorrow.

Would the water have caused a coil to fail ? Short out etc I can understand, but would water cause it to be fried inside ?
Cheers for the replies, its all been noted !

This kid is hell on legs buddy ! Dunno who he takes it after ?

Alan......

 

Well, considering in electrical terms, "fry" also means to "short" it's possible.

 

I did the same thing to mine on purpose because I wanted the engine clean to work on it. You probably just got water past the o-rings on the spark plug caps. Just get new o-rings and dry off the plugs.
Steve

 

Cheers for all the advice troops, its much appreciated

Removed the coil packs and as said, there was water on the other end of the "o" rings !! Not absolutely soaking, more like little droplets ?
Anyways, also removed the plugs, fitted new plugs, thoroughly dried the coil packs, banged it all back together and two days later, she hasnt missed a beat !
Looks like problem solved ?
Many thanks again, cracking forum !!
Alan...................

 

Glad to hear it!