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Engine Please help.

  • Thread starter Thread starter SGT Panosh
  • Start date Start date Mar 8, 2013

SGT Panosh

New Member
Mar 6, 2013
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Mar 8, 2013
#1
  • Mar 8, 2013
  • #1
I have changed #3 fuel injector, and ignition coil pack, wires, and plugs tested all ohms are good on plugs, plug gap checks out, thinking it could be mechanical at this point. there was oil on the #3 spark plug. Is there a good possibility that the valves are messed up. When I accelerate the car is lacking power and bogs down from time to time. No code has come up since I changed the ignition coil pack today but it is still acting up and I know it is just a matter of time before the code pops up again. Can a mechanical issue trip the computer to throw the misfire code?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,273
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Massachusetts
Mar 8, 2013
#2
  • Mar 8, 2013
  • #2
Yes. Leaking valve seal that leaks oil onto the plug could cause a misfire that would be picked up and cause a code to flash.
 

JB04v6

Member
Mar 13, 2013
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6
kansas city mo.
Mar 18, 2013
#3
  • Mar 18, 2013
  • #3
grandpa did a dollar at exhaust and if a valve was sucking it would pull the bill
by holding it against ex freely blowing at idle , a bad seat, seal,stuck,bent valve showed up as a pulling against ex guess as a pre compression test ? hope he's still giving to us, tho he has gone before us..
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,273
17,962
224
Massachusetts
Mar 20, 2013
#4
  • Mar 20, 2013
  • #4
What?
 

JB04v6

Member
Mar 13, 2013
42
0
6
kansas city mo.
Mar 21, 2013
#5
  • Mar 21, 2013
  • #5
Mustang5L5 said:
What?
Click to expand...

my grandpa told me of doing that for a valve issue. when the piston lowered on a bad valve it would suck in pulling the bill to the exhaust. this would be an ex valve i guess. not sure if it would work in this instance, but you see the reasoning don't you ? not sure in this case or if it was on model t's, but i recall the info so the only way to verify would be to try it. it does make sense to me and i'd try it since it costs nothing to ck if it applies .
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,273
17,962
224
Massachusetts
Mar 22, 2013
#6
  • Mar 22, 2013
  • #6
A compression test would be more helpful.

Then again, if you have oil coating the spark plug, you have a leaking valve seal. It's possible there is nothing mechanically wrong with the valve...you are just leaking oil past th seal, past the valve and onto the spark plug which is causing your misfire.
 

JB04v6

Member
Mar 13, 2013
42
0
6
kansas city mo.
Mar 23, 2013
#7
  • Mar 23, 2013
  • #7
Absplut
Mustang5L5 said:
A compression test would be more helpful.

Then again, if you have oil coating the spark plug, you have a leaking valve seal. It's possible there is nothing mechanically wrong with the valve...you are just leaking oil past th seal, past the valve and onto the spark plug which is causing your misfire.
Click to expand...

Absolutely, I just fondly flashed back to when pop was around, and his old time ways. unlike today's' tech. Didn't mean to revert to the stone age..lol sorry, still miss him.
mis aligned ring grooves, if 3 piece oil ring possibly that too. won't the PCV if blocked create pressure build up that would blow by even a good seal ?
Don't suppose clogged cat would figure in somehow ? No o2 issues till CAI and then lean bank 1 error I think it was, and after new o2's got @ 5 mpg more and performance. Pricey though effective in that instance..
 
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