Misfire after 10-15 seconds of idle
#1
Misfire after 10-15 seconds of idle
Ive been chasing this misfire for about 3 weeks now and it about has me ready to flip out. First of all, im getting a p0300-random/multiple misfire code. I put new plugs in and it fixed nothing. Today i pulled out the number 5 plug and it looked like it was brand new, and had raw gas on it. i pulled the wire off and tested it and its fine. i sprayed it w/ some wd-40 and put it back on and started the car up. Right at first it doesn't sound like its missin, but after about 15 seconds you can hear and feel it tone down and start missin. I pulled the number 5 plug back out and it looked like it was burnin.
Could this be a cam sensor??? ANY ideas please help ASAP!!!
Could this be a cam sensor??? ANY ideas please help ASAP!!!
#5
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yes this can be the cam sensor.
for example:
just for extra info!!!
One factor that is easy to miss, is that larger cams / lopey cam will cause the pcm to think the car is misfiring. The lope of the cam causes the cam position sensor to think a misfire is happening, causing the PCM to act erratic in trying to fix it. It causes your car to go into limp mode and dump in more fuel.
Its behaving just like when a tps (throttle position sensor) goes out!
so even if you are not cammed, yes this can be an issue.
also bad o2 sensors can cause this.
are you throwing other codes?
for example:
just for extra info!!!
One factor that is easy to miss, is that larger cams / lopey cam will cause the pcm to think the car is misfiring. The lope of the cam causes the cam position sensor to think a misfire is happening, causing the PCM to act erratic in trying to fix it. It causes your car to go into limp mode and dump in more fuel.
Its behaving just like when a tps (throttle position sensor) goes out!
so even if you are not cammed, yes this can be an issue.
also bad o2 sensors can cause this.
are you throwing other codes?
#6
nope...it threw an O2 sensor code and i replaced the sensor and it shut that code off but all im getting now is the p0300 random/multiple misfire....how can i check this cam sensor?
#7
actually do a compression test first before replacing any sensors same thing was happening to me and it turn out to be leaking valves it really boils down on how hard you drive your car my engine had a small portion of the valve broken of it seat causing it to miss fire samecodes and all do that first and save yourself alot headaces
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#8
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this same thing is happening to my car during the first few seconds of start up. I havn't gotten to change the plugs and wires yet but I threw a misfire code and a TPS sensor A low input code. I did put on a new throttle body so I checked it and found the blade was closing too far. I adjusted it so I don't think it's the TPS anymore but the car is still doin this. Is this something a shop can easily figure out because I'm dropping my car off at Conley's performance in a week for some other stuff and I need to get this figured out!
Oh yeah, my car just has a lid, throttle body, and catback
Oh yeah, my car just has a lid, throttle body, and catback
#10
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OH
...CRAP
well i hope that's not what's wrong with mine! When I did an oil change last weekend, I thought I heard a slight pop/crack(i'm really hoping it was nothing!) when I was pouring in the new oil but how the hell could pouring in oil do something like that!!!
...CRAP
well i hope that's not what's wrong with mine! When I did an oil change last weekend, I thought I heard a slight pop/crack(i'm really hoping it was nothing!) when I was pouring in the new oil but how the hell could pouring in oil do something like that!!!