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Need Help,engine started missing once it warms up.

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Old Nov 12, 2005 | 02:13 PM
  #1  
RodGT35th's Avatar
RodGT35th
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From: United States
Default Need Help,engine started missing once it warms up.

Had my 1999 GT 1 1/2 years now, 61000 miles, 5 speed. Anyway I baby this car, premium gas etc. Yesterday after it warmed up all of a sudden at low RPM under load only, the engine starts missing or skipping during acceleration. Once rpms are fairly high, most of the skipping/missing quits. I added a can of SEAFOAM and another tank of premium. I am getting NO check engine light. Plugs are still looking fine,don't believe they are fouling. Engine does hesitate slightly when you are in neutral and go to WOT. Sort of bogs out slightly,only slightly. However as stated earlier, under load only from 1 to 3000 RPM missing and skipping throughout acceleration.
Went out this morning took for her a spin. No problem while engine is cold. It ran fine, I thought the problem was gone. Then once it warmed up, BAM, it started again. HELP!!! Suggestions please.
I appreciate it.
Rod
Old Nov 12, 2005 | 03:16 PM
  #2  
Tim37's Avatar
Tim37
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From: AR
Default RE: Need Help,engine started missing once it warms up.

may be a coil pack goin bad.
Old Nov 12, 2005 | 05:08 PM
  #3  
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sllt1776
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Default RE: Need Help,engine started missing once it warms up.

i agree on those coil packs. it sounds like an electronic issue.
Old Nov 12, 2005 | 06:27 PM
  #4  
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Jglisson
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Default RE: Need Help,engine started missing once it warms up.

You are probably still showing a code. It takes confirmed hard code to throw on the CEL. Sounds like an ignition problem, especially with your mileage and the symptoms you described. If they are original plugs, change them.

New coil pack will run about $65. They came down on price here recently.
Old Nov 12, 2005 | 08:15 PM
  #5  
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RodGT35th
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Default RE: Need Help,engine started missing once it warms up.

If its a coil pack, would it show up as a code? Otherwise...1 of 8 to find!
I agree with you on the codes without CEL on. My old pre 96 code reader will show codes on my 93 ranger and 94 explorer without a CEL activation.
Old Nov 12, 2005 | 09:51 PM
  #6  
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Dan04COBRA
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Default RE: Need Help,engine started missing once it warms up.

If it's intermittent like you say, then it probably won't make a light come on.
Old Nov 12, 2005 | 10:12 PM
  #7  
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RodGT35th
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Default RE: Need Help,engine started missing once it warms up.

I was thinking more about the coil issue. If I'm not mistaken,at least as far as transformers and solenoids go. When and inductance device fails, it fails. So even though I too believe it's an electrical problem. I just don't know where to begin without a code. I cleaned my MAF sensor with electrical contact cleaner. I've got K&N filter on it. Had one on my 93 ranger for about 4 or 5 years. My MAF failed on my ranger and acted a lot like the Mustang. However I got a code light on my truck. I thinking those K&N filters get residual oil on the sensors??? Makes you wonder. I called Advance auto parts and asked them if they would hook up their code reader. They said not unless I was getting a check engine light.[:@] Thinking about going by and telling them it was on. Anyway I am still open to your comments Thank ya, Thank ya!
Old Nov 12, 2005 | 10:27 PM
  #8  
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mxracer1618
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Joined: Jun 2005
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Default RE: Need Help,engine started missing once it warms up.

i had a long *** thread on here awhile ago about my car doing that since i bought it. i did 1000 things to fix it.. i jus recentyl fixed it and i did the plug wires and coil packs in the same night then check all my replaced spark plugs and cleaned them up and one of them things worked cuz it runs perfect now. good luck with it
Old Nov 12, 2005 | 10:27 PM
  #9  
04BlueGT's Avatar
04BlueGT
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From: Georgia
Default RE: Need Help,engine started missing once it warms up.

I'd check the alternator and battery first. If you're battery is 'bout dead, then it may siphon off too much juice until the alternator is spinning very fast. Or, the alt may be going. This could explain why the problem goes away at higher rpm.

Also, I'd look at the IAT sensor. This could explain why the problem occurs after warm up.

Let us know what you find out. You can make us all a little smarter.
Old Nov 12, 2005 | 10:34 PM
  #10  
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Dan04COBRA
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Default RE: Need Help,engine started missing once it warms up.

BTW, there is no need for you to be using premium gas.



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