parked 3 wks-> washed engine-> miss fire

blueoval920001 · 08-21-2009, 09:03 PM

alright guys, need your help!!!

So i get to the place where i have to park my car temporarily, and its been sitting for i think about 3 weeks. decided to wash my engine as it was looking a bit grimey. covered battery, alt, major electrical connections, etc,. Did this all before i started it for the first time today so i would not be washing a warm engine. sprayed down with a mild solution of simple green and water, never used a high pressure stream of water to rinse. then used compressed air to blow dry electrical connections and nooks and cranny's. started her up and noticed she was missing a bit. not on every cycle of the engine but intermittently, but happening more times then it is not. let her run for a bit and took it down the street thinking someting just needed to dry off. few spins around the block and didnt seems to notice too much at low rpm, then as soon as i went passed 1/4 throttle to open it a bit it starts missing real bad. already read a few posts on here and i checked my COP's by unplugging them one by one and i could not really tell if there was a problem with one cause the miss does not sound like it is on every fire. does anybody have any ideas? or things i could try? thank you in advance

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Lowtryx · 08-21-2009, 09:41 PM

Throwing any codes?
I'm still willing to bet it's the Coils. I see a few every month after people wash them/extremely heavy rainfails (People around here like to drive through Puddles.. Go figure) where the Coils are fried. If it's not throwing any codes, I doubt it's a misfire. If so, see if you can't get a hold of an OBDII scanner or have the codes scanned.
Best bet. If you're NOT getting a MIL on your dash, chances are it's not a misfire.

blueoval920001 · 08-21-2009, 09:47 PM

no codes, and i checked the primary resistance on the coils and all checked out. if not a misfire then what could it be that would be masking as a miss. read afew more threads and there seamed to be plenty of people that have had missing and bad COP's and not throwing codes.

Brute03 · 08-21-2009, 10:12 PM

start pulling your coils, i'm almost positive you have some water in one or more of the plug wells

PROMETHEUS PRIME · 08-22-2009, 01:10 AM

Quote:

Originally Posted by Brute03

start pulling your coils, i'm almost positive you have some water in one or more of the plug wells

+1 TO THAT. Check the back 2 number 4 and 8. Most likely one or more is wet.

SmallFeesh · 08-22-2009, 02:07 AM

mine does this every time i wash the motor, no matter how carefull! A good long drive on the freeway always clears things up pronto! And I do mean a good long drive, like an hour straight of freeway drivin! Not in rush hour... lol.

cliffyk · 08-22-2009, 04:36 AM

Quote:

Originally Posted by SmallFeesh

mine does this every time i wash the motor, no matter how carefull! A good long drive on the freeway always clears things up pronto! And I do mean a good long drive, like an hour straight of freeway drivin! Not in rush hour... lol.

Running a COP with a shorted secondary (as in water in the plug well) can cause it to overheat and dramatically shorten its life.

Use some compressed air to blow out the plugs wells and dry the spring and boot...

SmallFeesh · 08-22-2009, 06:07 AM

lol... never said my way was the best way... just that it works!

Cliffy's way is the correct way to solve the problem.
If you have ready access to an air compressor that is.

SVTeeshirt · 08-22-2009, 12:54 PM

obviously he does feeshy he already said he used one to try it in the first place.

cliffyk · 08-22-2009, 04:53 PM

The problem with indiscriminate use of compressed air is that you can drive the water in to the "nooks an crannies"--disassembly and drying things off is different from just blowing air around. BTW, slathering things with WD-40 (Water Displacement-formula 40) is also a good way to "dry" things out.

Years ago I had a V-6 Jeep Commando that stalled if I drove it past the ocean, I'd pull the distributor cap and blow it and the rotor down with WD-40, then do the wires, and it would fire right up...