Randomly get P0300 codes.
Thread Starter
4th Gear
Joined: Jul 2015
Posts: 4
Likes: 0
Randomly get P0300 codes.
2002 C5 Z06 here.
Just went for a quick drive around town for 10 minutes. I saw I had a check engine light about 5 minutes into the drive. When I looked at the onboard code reader it gave a PCM P0300 pending which is random misfire.
I had this happen to me a few weeks ago, so I changed the plugs to TR6 and gapped them at .041. Wires look OK. Happens very seldomly and definitely only once every few days, it does not return when cleared.
Any ideas what would cause this? Car is cammed and is running perfectly otherwise.
Just went for a quick drive around town for 10 minutes. I saw I had a check engine light about 5 minutes into the drive. When I looked at the onboard code reader it gave a PCM P0300 pending which is random misfire.
I had this happen to me a few weeks ago, so I changed the plugs to TR6 and gapped them at .041. Wires look OK. Happens very seldomly and definitely only once every few days, it does not return when cleared.
Any ideas what would cause this? Car is cammed and is running perfectly otherwise.
Burning Brakes
Joined: Jun 2012
Posts: 803
Likes: 42
From: Destin Florida
2002 C5 Z06 here.
Just went for a quick drive around town for 10 minutes. I saw I had a check engine light about 5 minutes into the drive. When I looked at the onboard code reader it gave a PCM P0300 pending which is random misfire.
I had this happen to me a few weeks ago, so I changed the plugs to TR6 and gapped them at .041. Wires look OK. Happens very seldomly and definitely only once every few days, it does not return when cleared.
Any ideas what would cause this? Car is cammed and is running perfectly otherwise.
Just went for a quick drive around town for 10 minutes. I saw I had a check engine light about 5 minutes into the drive. When I looked at the onboard code reader it gave a PCM P0300 pending which is random misfire.
I had this happen to me a few weeks ago, so I changed the plugs to TR6 and gapped them at .041. Wires look OK. Happens very seldomly and definitely only once every few days, it does not return when cleared.
Any ideas what would cause this? Car is cammed and is running perfectly otherwise.
Has it been tuned after the cam install? If so did the tuner change the threshold on when the P0300 is triggered ? A miss fire is usually triggered by the crank sensor and a cam with even just a little more duration etc. will set that code.
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Joined: Dec 2010
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2020 Corvette of the Year Finalist (performance mods)
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this is very possible, my car did the same thing after the cam install until I had it tuned... since the plugs and wires are good, take a look at the coil/injector harness on the driver side where it runs behind the intake... there is a useless bracket near the back of the fuel rail and the harness is prone to rubbing on that bracket and over time can eventually damage the wiring and give you all sorts of problems... I removed that bracket the first time I took my intake off
Thread Starter
4th Gear
Joined: Jul 2015
Posts: 4
Likes: 0
this is very possible, my car did the same thing after the cam install until I had it tuned... since the plugs and wires are good, take a look at the coil/injector harness on the driver side where it runs behind the intake... there is a useless bracket near the back of the fuel rail and the harness is prone to rubbing on that bracket and over time can eventually damage the wiring and give you all sorts of problems... I removed that bracket the first time I took my intake off
