P0300

[Chilliwack 42]

A few weekends ago my car threw a P0300 code. I have Comp Mutha Thumpr Cams so it was hard to tell when it was missing. I've had the cams for a few years and they we're installed by my dealer so I don't suspect an install issue. The only thing I have done to my car this year was replacing the stock clutch and flywheel with an Exedy setup. Oddly enough my car ran it's best time 12.24 @110 while it was throwing a misfire code.

I'm going to check the plugs and COP's this winter and likely replace the plugs since I'm going to the trouble of pulling them. It probably wouldn't hurt to change the fuel filter and check the injectors as well.

I've been doing some reading up on here and I'm just wondering if I may require a Misfire Monitor Neutral Profile Relearn. From what I've read it seems changing the clutch and flywheel on a 5.0L can cause this code. I'm curious if the same goes for a 4.6L.

 

[ArtQ]

The 4.6 has the crankshaft trigger on the front of the engine. The 5.0 has it on the rear. You won't need a relearn. Fresh sparkplugs will most likely solve the problem.

 

[GhostPsalm]

I got that code a few weeks back, cleared the code and hasn't come back...sometimes it is just random.

I've had the Comp Mutha Thumpr Cams for 4,000 miles and no probs

 

[Cammed 05]

I had that problem a few weeks ago. I would clear it and it would come back sooner or later. I couldn't tell due to the hotrods but sometimes it felt like a misfire. Finally did some data logging with Bama, they sent a new file to take care of the misfire after taking a look. Car feels much better now.

Just a thought. Though it is time for plugs again. -_-

 

[Chilliwack 42]

Thanks guys, I wasn't sure where the crank sensor is on a 4.6. I'll be replacing the plugs and boots this winter. I'll test the coils as well just to rule them out. I doubt it would be the cams since I've been driving with them for years without a code thrown.

I'm planning on a bunch more mods this winter including a dyno tune, so I'm hoping this will all get sorted out and I'll be able to reach my goal of running 11's N/A next year.

 

[GhostPsalm]

what mods do you have man? I dyno'd at 320rwhp and just recently added an aluminum driveshaft

**dyno'd on 93 race tune with 87 octane gas in the car so who knows what it would have been with 93 octane on the 93 race tune lol

 

[Chilliwack 42]

JLT CAI II, 93 Race Bamachip Email Tune, BBK LT Headers, BBK O/R X-Pipe, Flowmaster Mufflers, Steeda CMCV Delete Plates, Comp Mutha Thumpr Cams, Steeda Pulleys, BMR Rad Support, BMR K-Member and A-Arms, BMR Upper Arm, Steeda Billet LCA's and Relocate Brackets, Coastline Driveshaft, 4.10 Gears, Moser Axles, Truetrac Posi, Koni Yellows, Eibach Drag Springs, MSD Ford Launch Master.

I've run a best time of 12.24 @110 MPH. I'll be switching to 4.56's this winter. I find with 4.10's I'm shifting in to fourth before the traps, I'd rather be at a higher RPM where I'm making more power. I'm also planning on upgrading to a JLT 3 along with a Cast JPC Intake and a finally getting around to get a dyno tune.