P1336 — Misfire Rate Catalyst Damage Fault - Bank 1

P1336 — Misfire Rate Catalyst Damage Fault - Bank 1. A fault in the engine misfire monitoring. Short, gentle driving to a shop is usually possible. Typical causes: low compression in the affected cylinder(s), incorrect fuel pressure or a weak fuel pump, clogged or leaking fuel injector.

For Ford vehicles

crankshaft/camshaft sensor – range/performance problem

powertrain (engine/transmission)

Is it safe to drive?

Drive with caution Drive only as much as necessary. An active misfire sends unburned fuel into the exhaust and can destroy the catalytic converter within hours, especially if the Check Engine Light is flashing — in that case stop driving and diagnose immediately.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm P1336 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the engine misfire monitoring for damage, corrosion, chafing or poor contact.
Subsystem check Read per-cylinder misfire counters in live data to identify the affected cylinder(s).
Subsystem check Swap ignition coils or injectors between cylinders and see if the misfire follows the part.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P1336 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P1336 (parts and labor, USD, independent shop rates): Clean or replace a fuel injector: $200–$600; Replace an ignition coil: $150–$380; Engine mechanical repair (compression): $800–$2,500; Replace spark plugs: $90–$250. Overall, fixing P1336 usually costs between $90 and $2,500. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

What is the most common cause of P1336?

The most common causes are: low compression in the affected cylinder(s), incorrect fuel pressure or a weak fuel pump, clogged or leaking fuel injector.

Is it safe to drive with P1336?

Drive only as much as necessary. An active misfire sends unburned fuel into the exhaust and can destroy the catalytic converter within hours, especially if the Check Engine Light is flashing — in that case stop driving and diagnose immediately.

What does OBD2 code P1336 mean?

How do I diagnose P1336 myself?

Start with a scan: confirm P1336, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the engine misfire monitoring, and verify the suspect component against live data before buying parts.

Will P1336 clear itself?

Sometimes P1336 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

When your check engine light comes on and a scan tool reveals code P1336, it means the engine control unit has detected a pattern of misfiring that is severe enough to risk damage to the catalytic converter on Bank 1 — the engine bank that contains cylinder number one. This is not a code that triggers from a single glitchy sensor reading. The ECU requires the misfire condition to repeat multiple times under specific load, rpm, and temperature conditions before it will store P1336 and illuminate the warning lamp. Think of it as the car's way of telling you the problem is real and recurring, not a fluke.

The engine misfire monitor runs continuously while you drive. It watches for irregularities in combustion by tracking crankshaft acceleration — each power stroke should accelerate the crank smoothly, and any stumble gets logged. When the monitor sees enough misfires from cylinders in Bank 1 to threaten the downstream catalytic converter, it sets P1336. The freeze frame data stored alongside this code is your roadmap: it captures engine load, RPM, coolant temperature, vehicle speed, and throttle position the instant the fault was confirmed. Use those numbers to recreate the driving conditions during your diagnosis. Bank 1 refers to a specific side of the engine block, and which side that is varies between manufacturers and engine configurations. Always confirm Bank 1 location for your particular vehicle before proceeding with testing or repairs.

Common Symptoms of P1336

Engine shakes noticeably at idle, feeling rough or uneven
Fuel economy drops noticeably compared to normal
Vehicle bucks, jerks, or hesitates when you press the accelerator
Acceleration feels weak or sluggish
A stronger-than-usual fuel smell comes from the exhaust
Check Engine Light is illuminated, and it may flash continuously under heavy load

What Causes P1336?

A fuel injector that is clogged, restricted, or leaking on one of the Bank 1 cylinders
Low compression in one or more cylinders on that bank, caused by worn rings, bad valves, or a blown head gasket
A faulty crankshaft or camshaft position sensor producing erratic timing signals
Spark plugs that are worn out, fouled with carbon deposits, or have cracked insulators
Fuel pressure that is too low or inconsistent, often due to a weak fuel pump or a failing fuel pressure regulator

How to Diagnose P1336

Plug in an OBD2 scanner and confirm that P1336 is stored in the engine control module. Save the freeze frame data immediately — this snapshot of engine conditions tells you exactly what was happening when the fault triggered, and you will need to replicate those conditions later to verify your fix.
Check for any other diagnostic trouble codes stored alongside P1336. Related codes for fuel delivery, ignition, or sensor faults often point directly to the root cause. Also search for technical service bulletins specific to your make, model, and model year — many P1336 cases have documented factory fixes or software calibrations that a dealer or qualified shop can apply.
Perform a thorough visual inspection of the wiring harness and connectors related to the fuel injectors, ignition coils, and crankshaft position sensor on Bank 1. Look for damaged wires, corrosion at the connectors, chafing from rubbing against engine components, or loose pins that could interrupt the signal.
Access the live misfire counter data on your scanner. This shows which cylinder or cylinders are contributing to the fault. A single cylinder misfiring consistently narrows the problem to that cylinder's ignition, fuel, or compression system.
If the data points to a specific cylinder, try swapping the ignition coil or fuel injector with one from a cylinder on the opposite bank. Clear the code and run the vehicle. If the misfire counter moves to the other cylinder, you have identified the failed component.
After any repair or part swap, clear the code and complete a full drive cycle that includes the conditions recorded in the freeze frame — particular load, speed, and temperature ranges. Only confirm the repair is complete when P1336 does not return after this verification drive.

Repair Options and Costs

The right fix depends entirely on which underlying component is causing the misfire. The following price ranges cover parts and labor at an independent repair shop in US dollars:

Fuel injector cleaning or replacement (one injector, Bank 1): $200–$600
Ignition coil replacement (one coil): $150–$380
Engine mechanical repair addressing low compression: $800–$2,500
Spark plug replacement (set of four): $90–$250

Total Cost to Fix P1336

Depending on which part is actually faulty, expect to spend between $90 for a basic spark plug replacement and up to $2,500 for internal engine mechanical work. The most likely culprits — a single failing injector or ignition coil — fall in the $150 to $600 range. The most important thing you can do is spend time on accurate diagnosis before spending money on parts. Guessing and replacing multiple expensive components hoping one of them fixes P1336 is a costly approach that rarely pays off.

Can You Drive with P1336?

Proceed with caution. The ECU sets P1336 when misfires are sending unburned fuel and raw hydrocarbons into the exhaust stream. This extra load can overheat and destroy the catalytic converter in a matter of miles if the condition is severe. If the Check Engine Light is flashing — not just steady — that indicates a continuous misfire happening right now, and you should stop driving immediately and have the vehicle towed to a shop. Even with a steady light, limit your driving to getting to a repair facility and avoid hard acceleration or heavy loads until the issue is resolved.