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P300, P302, P308, P316, P1336 – 2003 Lincoln Aviator 4.6L Misfire Diagnosis & Repair Advice

Model: 2003 Lincoln Aviator Fault Code: P1336 Posted: 2010-03-19 22:06

I recently encountered a persistent engine misfire issue on my 2003 Lincoln Aviator with a 4.6L V8 engine (91,000 miles). The problem began about one month and a half ago when the vehicle started hesitating between 50–55 mph—no check engine light was present. I took it to Bill Currie Ford Lincoln Mercury in Tampa, FL for diagnostics. Due to long wait times (3 hours), I left without service. Later, the service advisor called and advised replacing four spark plugs, four coil packs, and four coil boots for cylinders 1, 3, 5, and 7—totaling $788 for parts and labor. I declined, citing concerns about over-repair. When I returned to pick up the vehicle, it failed to start. I noticed the fuel tank was nearly empty. Inside, the service advisor admitted they would investigate. After 10 minutes, they managed to start it with minimal fuel—likely due to a fuel system issue. Three days later, the car began running rough at all speeds. I then replaced all eight spark plugs and coil packs myself (Motorcraft brand plugs at $2.99 each, plus tax; coils purchased from dealer parts department). A friend’s mechanic completed the work—after which symptoms disappeared for a week. However, one week later, the engine began running rough again, and the check engine light illuminated with three codes: P0301 (cylinder 1 misfire), P0306 (cylinder 6 misfire), and P316 (misfire during first 1000 RPMs). My mechanic switched plugs and coils between cylinders 1→3 and 6→4 to test if the misfires would transfer—but no change occurred. Compression tests showed normal readings, and no leaks were detected. A strong gasoline smell is also coming from the exhaust—though catalytic converter was replaced at 80,000 miles. Next, I replaced the crankshaft position sensor (P1336 code appeared after replacement). However, misfire codes persisted: P0301 and P0306 remained, and new codes emerged: P0302, P308, and P1336. I recently ordered six new fuel injectors for cylinders 1 through 6. After installation (with cleaning and replacement of O-rings on the remaining six), the P0301 and P0306 codes disappeared—but three new codes appeared: P300 (multiple misfires), P302, P308, and P316. My question is: Are these new codes indicating that the remaining six injectors are faulty? Or could this be a PCM malfunction due to repeated misfire events? I’m particularly confused by the reappearance of P1336 after replacing the crankshaft sensor—should I revert back to the original sensor and reset the PCM? What should I do next? What would you recommend? Should I replace all six remaining injectors, or is it better to consult a more experienced mechanic for a full diagnosis? Thank you in advance for your insights! Eduardo

Related fault codes

P1336

Comments (7)

Anonymous 2010-03-20 08:04

I don't have the P1336 code definition on hand—could this be related to flex fuel operation? Are you using E85 fuel in Tampa? E85 can damage injectors and internal components if the vehicle isn’t designed for it. Just a note worth considering.

Anonymous 2010-03-20 08:42

The crankshaft position sensor was purchased from Pep-Boys. For context, 95% of the time when a 4.6L Lincoln Aviator logs misfire codes and identifies specific cylinders, it's not due to a faulty crank sensor. If a jobber-grade sensor was installed instead of the original factory unit, it may perform poorly. I don’t know your budget, but I’d advise against replacing more parts without a competent diagnosis. The exhaust smell indicates rich fuel mixture from ongoing misfires—this could lead to catalytic converter failure if not addressed immediately.

Anonymous 2010-03-20 08:45

In many Ford and similar vehicles, severe and repeated misfiring can generate false crankshaft sensor faults. This means your P1336 code may be a symptom of the underlying misfire issue rather than an actual failure of the new sensor—so you're essentially stuck between whether the replacement part is defective or if the problem stems from deeper engine issues.

Anonymous 2010-03-20 15:02

Thanks for your responses! I confirm this vehicle is not a flex fuel model—it's been running on regular 93 octane gasoline since purchase, with Shell V-Power used about 70% of the time. In Tampa, FL, most gas stations indicate their fuel may contain up to 10% ethanol. I bought the crankshaft sensor at Pep-Boys but still have the original one. Should I reinstall it? Would a PCM reset be required after reinstallation? Today I scanned the vehicle again and was surprised: I now see P300 (multiple misfires), P302, P308, P316—plus P1336 (indicating crank sensor failure) and a new code P0307 (cylinder 7 misfire). This is very unusual. I’ve just ordered six brand-new fuel injectors. Since replacing the original ones on cylinders 1 and 6 resolved those issues, I believe they may be faulty. However, I will now consult a different mechanic for re-inspection and full diagnostics. I’ll update everyone here as progress unfolds. Thanks again for your help! Eduardo

Anonymous 2010-03-20 15:18

I wouldn’t recommend purchasing crankshaft sensors from aftermarket suppliers—many have caused worse drivability issues on GM and Ford vehicles. Aftermarket parts often fail to match factory performance or compatibility. You could try reinstalling the original sensor you removed, though there’s a risk it may have been damaged during removal. That said, this approach is risky without proper inspection. I understand your decision to replace six injectors—but that investment might be better spent elsewhere unless removing the two faulty ones caused damage to the remaining injectors. Also, were the coils and spark plugs purchased from reputable sources? I’ve seen cases where a 'new' coil from a parts store was actually defective—leading to persistent misfires. Additionally, on many Ford engines, only replacing the boot without changing the coil or vice versa can cause carbon tracking on spark plugs, resulting in misfiring. Aftermarket boots may also be too short and interfere with proper plug positioning.

Anonymous 2010-03-20 16:40

Thanks for your response! I bought the plugs at AutoZone (Motorcraft brand—8 units at $2.99 each, plus tax) and coils from the dealer parts department (8 units at $70 each, total $623). The dealer previously quoted $788 for just four plugs and four coils. When I first saw P0301 and P0306, I swapped coils between cylinders 1→3 and 6→4 to test misfire transfer—but the codes stayed in cylinders 1 and 6. This makes me question whether defective coil packs are the root cause. Tomorrow, I will reinstall the original crankshaft sensor (from before), perform a full fuel system flush, replace the fuel filter, and conduct a fuel injection cleaning. I’ll keep everyone updated on progress. Thanks again for your guidance!

Anonymous 2010-06-02 20:59

Eduardo—surprised no one mentioned that coil packs on the 2003 Lincoln Aviator are typically covered under an extended warranty up to 120,000 miles. If your vehicle is throwing misfire codes like P0301 or P0306, the dealer should have replaced them at no cost under warranty. I had the same issue and my coils were replaced free of charge by the dealership.