could this be internal
#1
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could this be internal
i have had a miss at idle for sometime now, and i scanned it with a live scan genisis. the car has been tripping a code for a while, the dreaded p0420 cat code. i was told this wouldnt cause a miss. but when i scanned it it was showing misfires happening at idle, but never once actually threw a misfire code. i did the usual plugs and wires and routine stuff, and havent fixed it yet. any ideas? i am hoping its not internal. car has 41k on it, it a 02 ls1. any help is appreciated guys.
scan also said spark was between 16 and 20 degrees at idle with an a/f of 14.3
scan also said spark was between 16 and 20 degrees at idle with an a/f of 14.3
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I think the cat can cause the miss fire,the cat sensors decides what to do as far as engine paremeters, A/F ratio, timming etc... either sensor is bad or cat. it's cheaper to change cat sensor then cat ... .02
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there is a sensor on the cat? btw i took the car out today, and if you hit it full throttle, from a dead stop, the car completly bogs down and doesnt get going for about five seconds. does anyone know exactly what the po420 cat code makes the motor do different? i am about ready to trade this car in i am sooo frustrated.
#4
No their is no sensor in the cat, he is referring to the front 02. P0420 is just letting you know that the cats aren't working either because you removed them/they are clogged/ or your rear 02's are shot.
A miss at idle can come from bad plugs, bad wires, or a faulty coil just to name a few.
Replace the plugs and make sure you get all the wires on there nice and tight.
A miss at idle can come from bad plugs, bad wires, or a faulty coil just to name a few.
Replace the plugs and make sure you get all the wires on there nice and tight.
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will the car run different with that p0420 code active? because it just seems like it is running rich. so could i just have all the cat related stuff tuned out and be done with that? i was gonna put longtubes on next week
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what if the cat itself is shot, or clogged, would that make it run different? i am going to compression test it tommorro just to rule it out for peace of mind. what do you guys think the compression should be at for and ls1?