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High hopes maybe crushed: Check Engine Light

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  #1  
Old 06-15-2009, 06:03 PM
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Default High hopes maybe crushed: Check Engine Light

it's monday and I just got this 2003 GT on Sat. It's a automatic.

Drove just fine. Worked like a champ till today.

The check engine light just blinked for a few seconds then stayed solid and doesn't go away when I turn off the car and turn it back on.

It feels like it's taking longer to shift and longer to accelerate then before. it's much more rough when it shifts to and I can certainly feel it a lot more. I can hear a pulsing sound from the engine and from time to time I get a shudder like something got stuck for a split second and got unstuck.

It's unmodified aside the snorkle/siliencer has been removed (I found it in the trunk) and the dealer replaced the alternator some point in it's recent past.

I found a loose hose on the air intake (last hose away from the TB). I tightened that up and it seemed to help a little but most of it is still there.

Help!
 
  #2  
Old 06-15-2009, 06:09 PM
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If you don't have a tuner like Diablo or SCT which I assume you don't since you just bought it...take it to autozone and have them pull the code for you. You might have better luck with someone helping if you have the code.
 
  #3  
Old 06-15-2009, 06:11 PM
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cool. Didn't know they'd do that for me. i'll do that in the morning.
 
  #4  
Old 06-15-2009, 06:28 PM
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if you just bought it from a dealer i would take it back and have them look at it
 
  #5  
Old 06-15-2009, 07:05 PM
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yes, if you just bought it, take that back to the dealer.
 
  #6  
Old 06-16-2009, 12:23 AM
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Originally Posted by Leonide
yes, if you just bought it, take that back to the dealer.
+1
 
  #7  
Old 06-16-2009, 05:12 AM
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Flashing light means missfire. Go to any parts store and they will pull the codes for you for free. Bring some paper and pen and write them down and we can help you out from there. I depending on what comes up you might need to just do a basic plug swap or who knows. But don't have them clear the codes incase you need to bring it back to the dealer.
 
  #8  
Old 06-16-2009, 07:28 AM
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Code reader said cylander 5 misfire.

However, I put the snorkle back on prior to driving to O'rileys and it drove like nothing was wrong. Could the lack of the snorkle have caused the cylander to misfire?
 
  #9  
Old 06-16-2009, 07:31 AM
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nope
replace your plugs. They're done. I got 60k out of the factory 100K mile plugs. Don't expect that they'll be good that long in reality. Grab yourself another set of plugs and get to work.
 
  #10  
Old 06-16-2009, 07:34 AM
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*nod* I'll get some then and work on swapping thme out.

you guys got any favs for a brand?
 
  #11  
Old 06-16-2009, 07:38 AM
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stock replacement autolites should be fine don't get anything fancy it's not worth it
 
  #12  
Old 06-16-2009, 07:54 AM
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Autolites or NGK are both good and cheap. And pull the silencer back off it will not hurt anything, but performance well a horsepower or so at least lol. They also have a new highflow filter out called the spectra that costs almost the same as a paper filter. Might wanna toss a new one of those in there while your at it.
 
  #13  
Old 06-16-2009, 08:13 AM
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know anything about the E3 Diamond fire plugs?
I heard some things about them from the parts guy at O'riley's and their selling them for about a dollar more than the autolights.
 
  #14  
Old 06-16-2009, 08:46 AM
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I just used motorcraft plugs. I figure you can't really go wrong with ford parts.
 
  #15  
Old 06-16-2009, 08:51 AM
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I want to to double check what i think I'm doing. Somethings look deceptively simple after all.

Trace the spark plug wires to where the plugs are located, take the boot off, take the wire off, remove the plug with a socket, double check the spacing on the new plug, screw in the new plug according to directions on package, reattach wire, put boot back on, repeat for each cylander.

Anything I miss? I haven't traced the wires yet so I don't know if I'll have to jack the car up. Will that be needed?
 
  #16  
Old 06-16-2009, 08:57 AM
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That's pretty much it. You probably won't have to jack up the car.

Though, if it's still misfiring you may need new wires and/or a new ignition coil. That's what was causing my car to misfire.
 
  #17  
Old 06-16-2009, 08:58 AM
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your 03 don't spark plug wires it's coil on plug/individual coil per cylinder that sit right on the valve covers above the plugs
 
  #18  
Old 06-16-2009, 09:03 AM
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*nod* same idea though. Find the plugs and get to work. Just mentioned wires as a means to locate them since I obviosuly haven't yet.

Am I going to need anything special to do this? I've got a decent socket wrench set but I don't know if i need a special tool or some such.
 
  #19  
Old 06-16-2009, 09:22 AM
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No plug wires on these motors. They are a cop (Coil on plug) setup. You will have to remove your fuel rails on each side of the motor to access the cop. Make sure you relieve to pressure on them by bleeding the Schrader vavle on the end of the rail on the pass. side of the motor first. WATCH YOUR EYES !!. All the cops are the same so it doesnt matter where they go. Remove the cop and pull and wiggle it up out of the whole, some of them might be a pain. Remove each plug, gap the new ones to .045. The plugs are steel and the head is alumiun, apply a small amount of anti-seize to the threads on the new plug (you will thank me next time) Install plug and DO NOT OVER TIGHTEN Repeat 7 more times Good Luck
 
  #20  
Old 06-16-2009, 04:10 PM
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Fuel rails do not have to come off to do this. Just take out the single bolt that holds the coil on and then press down and pull it out from under the fuel rail. Don't worry about hurting them just push them down and yank them out. After that the spark plug is right there. All you need is a socket wrench, a 6" extension or two 3" ones and then a spark plug socket.

The coils are right on the top of the motors and are black and are somewhat under the fuel rails.
 
  #21  
Old 06-16-2009, 04:20 PM
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got it. I've got all the tools you listed and I picked up a set of plugs. THe engien needs to cool off so I'll probably change them out tomorrow since it will be dark by the time the engien is cool.
 
  #22  
Old 06-16-2009, 04:53 PM
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Originally Posted by spike_africa
Fuel rails do not have to come off to do this. Just take out the single bolt that holds the coil on and then press down and pull it out from under the fuel rail. Don't worry about hurting them just push them down and yank them out. After that the spark plug is right there. All you need is a socket wrench, a 6" extension or two 3" ones and then a spark plug socket.

The coils are right on the top of the motors and are black and are somewhat under the fuel rails.
I don't know how you can get to the rear passenger plugs without pulling the fuel rail off.. I had no problem with the drivers side, but the passenger side is all tucked in the back..
 
  #23  
Old 06-17-2009, 06:09 AM
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Just by pushing it down and turning it so it can slide out. Trust me the rails don't have to come off to do this.
 
  #24  
Old 06-17-2009, 07:09 AM
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Originally Posted by spike_africa
Just by pushing it down and turning it so it can slide out. Trust me the rails don't have to come off to do this.
I would have to agree. I didn't ave to take mine off when I changed out the plugs. I would also recommend blowing out all the debris and crap from the plugs before you remove them.
 
  #25  
Old 06-17-2009, 07:57 AM
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Originally Posted by spike_africa
Fuel rails do not have to come off to do this. Just take out the single bolt that holds the coil on and then press down and pull it out from under the fuel rail. Don't worry about hurting them just push them down and yank them out. After that the spark plug is right there. All you need is a socket wrench, a 6" extension or two 3" ones and then a spark plug socket.

The coils are right on the top of the motors and are black and are somewhat under the fuel rails.
This is exactly 100% correct info. Don't make it hard on yourself. BE SURE to use anti-seize on the plugs. You don't want to pull threads out with them next time.
 
  #26  
Old 06-26-2009, 08:28 AM
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Okay, I'm chaning otu the plus but I had a odd thing happen.
I let the car sit for a day or two before starting it again and it's behaving almsot normal.

i say almost because the acceleration seems very sluggish. I can get up to 2-3k rpms from a stop and only be around 30 mph.

Also there is a noise I'm not sure how to describe when I hit the accelerator even semi-hard. Someone said it sounded like a exaust leak but it's in the wrong palce. kinda a ticking/raspy/ pulsing noise.

No check engine lights come up but I feel like something is wrong with the car but I don't know what. Any ideas?
 
  #27  
Old 06-26-2009, 10:14 AM
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Is the noise coming from the engine, because if it is I hope to hell you did not strip out the threads on one of those plugs and are losing compression threw there.
 
  #28  
Old 06-26-2009, 02:56 PM
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I went and had a profesional install the plugs.

Yes the noise was coiming from the engine bay.

I tried a computer trick though. I upluged the battery for 5 minutes, connected it up again and it was purring after that. Is it possible the computer tried to over correct for the missfire?

Also, it's a little strange but it was behaving better before the plug got changed but after I reset the computer. Is it probably just not used to the new plugs and I need to reset the computer againf or it to accept them?
 

Last edited by dkt0404; 06-26-2009 at 03:00 PM.
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