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Fuel on spark plug..??

  • Thread starter Thread starter RioRed4v
  • Start date Start date May 24, 2007
R

RioRed4v

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#1
  • May 24, 2007
  • #1
Last night I took my intake and headers off since I needed to do a few things. When I got the intake off, there was a strong smell of fuel. Wasnt to worried since it usually smells close to that, but when i got my spark plugs out, there was 1 or 2 that kinda looked a little wet on the threads, not on the ceramic part, and the ceramic part was pretty much white (like they hadnt be burning), but there was some black deposit around the outside so it appears they were firing.

The car seems to run a tad rich, but nothing overly crazy. When I had it tuned a few months back, AFR was around 12.9. The injectors were used, but I replaced with new caps and o-rings. Another post I found on here mentioned to a compression test, since I guess a cracked ring can cause lots of fuel on the plug, but my compression test from a few months ago checked out fine. Pretty equal across the board. The car drives fine, kinda lugs down in the lower RPM's, but I also have 2.73's and a cam that was designed around me using 3.90s', so i figure thats why i lugs down.

Any ideas what the issue could be here?
 

cjones

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#2
  • May 24, 2007
  • #2
Leaking Injectors??
 
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RioRed4v

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#3
  • May 24, 2007
  • #3
thats kinda what i was thinking also, but i wasnt sure if the car would feel bad, or how FP would react and so on.
 

cjones

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#4
  • May 24, 2007
  • #4
if it's barely leaking the car could still run ok(the computer would compensate) but when the engine is turned off the residual pressure in the fuel rail leaks past the bad injectors and fouls the plug.
 
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RioRed4v

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#5
  • May 25, 2007
  • #5
every now and then i've noticed that when i turn the key to on position, i see my FP jump up to where it should, and then it'll drop back down about half-way and hold there until i start the car. when the car is started it'll hold pressure fine, but sometimes when its just sitting in the on position, it'll drop and then hold.

sound like its leaking?
 

cjones

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#6
  • May 25, 2007
  • #6
the fuel pump turns on for 2 seconds when you turn the key to the RUN postion then shuts off until you go to start the car. it's called priming the system.

the pressure may drop some but should not drop more than about 5psi in one minute.

if it drops more there may be a leak. possible causes; Fuel Pressure Regulator, Injectors, Fuel Pump
 
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RioRed4v

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#7
  • May 25, 2007
  • #7
i think it drops more than 5psi from the intial prime to when it gets started. regulator and pump are both brand new also.. seeming like i should swap out the injectors that i may think are bad.

thanks for the help
 
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