Possible to have a misfire w/o a code?
07-26-2008, 10:04 PM
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Possible to have a misfire w/o a code? Is it possible to misfire or simply be down a cylinder w/o throwing a code? If so, should i be able to just take it in to a local shop and have them check it out... cause i'm not really sure how you're supposed to diagnose it w/o a code.
07-26-2008, 10:13 PM
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from what i know you can have a slight missfire with out a code.
i had a 98 supercharged gtp a few years back and had a wire fry so i put a new set of colder plugs to fight knock and a new set of autolite wires and car was fine then about a month later i developed a miss. i thought it was the plugs because the wires where new and after swaping plugs a few times i swaped a cheap set of wires and i fixed it with out it ever throwing a code.
i had a 98 supercharged gtp a few years back and had a wire fry so i put a new set of colder plugs to fight knock and a new set of autolite wires and car was fine then about a month later i developed a miss. i thought it was the plugs because the wires where new and after swaping plugs a few times i swaped a cheap set of wires and i fixed it with out it ever throwing a code.
07-26-2008, 10:29 PM
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Aight so if i don't really have my own time and i feel most comfortable letting a mechanic play with it, could i just take it to a local shop? Shouldn't they have some type of balance test for it?
Last edited by Vrbas; 07-26-2008 at 11:17 PM.
07-27-2008, 12:47 PM
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thry can do a cylinder balance test with a scanner and be able to get it narrowered down to that cylinder. it may not be able to specify if it is ign or fuel, but atleast get you in the ballpark
07-27-2008, 01:39 PM
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1. Get a squirt bottle filled with water.
2. Start motor and let it come up to temp.
3. Spray water on each exhaust port on the manifold / header and the water should boil and evaporate almost immediatly. If you have a cylinder that doesn't do this then you have a great start as to which cyinder to check.
I've used this technique before.
*Doesn't always work but It can give you a good place to start*
2. Start motor and let it come up to temp.
3. Spray water on each exhaust port on the manifold / header and the water should boil and evaporate almost immediatly. If you have a cylinder that doesn't do this then you have a great start as to which cyinder to check.
I've used this technique before.
*Doesn't always work but It can give you a good place to start*
07-27-2008, 11:26 PM
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I'd at least give it a whirl yourself before you go to a mechanic. You more then likely have a bad wire or it is touching metal or a bad spark plug. I had an inconsistant miss that didn't throw codes and it ended up being a crack in a plug. Should be a relatively quick fix for you if you have ever changed plugs (20-30 mins). Thats what your mechanic will start with.
