for starters P1301 after replacing intake cam

 

the 1301/1302 are not random misfire codes, those mean misfire severe enough to cause emission level increase and then misfire severe enough to cause catalyst damage, respectively. you could always try the typical procedure of moving the coils from cylinder to cylinder to see if the misfire follows the coils, but the recent timing chain work seems more suspect.

 

here's the page from the service notes:

Misfire P0300
P0301
P0302
P0303
P0304
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected
Description
A misfiring cylinder can be detected by analysing crank speed variation. As a result of a combustion event there
will be a net acceleration of the crankshaft. Subsequent to a misfire event the engine will decelerate over the
period following the missed cylinder event.
Speed changes can be characterised by observing changes in the time period for a fixed angle of rotation after
firing events. A significant change in this period, assessed by comparison to previous periods, may be attributed
to misfire on a known cylinder.
Component connections '06 M.Y. in brackets
Connector Description ECU Pin ECU Connector
1 Supply Voltage Coil 1 Coil 2 Coil 3 Coil 4
2 Ignition Coil Feedback 22 (F3) 22 (F3) 22 (F3) 22 (F3) 52 Way (Right)
3 Coil Output (Logic) 52 (G1) 26 (G4) 47 (G3) 48 (G2) 52 Way (Right)
4 Ground
Malfunction Criteria
The operation of all the misfire codes is the same, the last digit relates to the misfire involved i.e. a code P0303
indicates there is a problem with coil number 3. P0300 indicates the misfire is random and not linked to one
particular cylinder.
Enable Criteria:
• Battery voltage between 10 – 16 V
• Coolant temperature between -10 – 120°C (14 – 248°F)
• Engine speed between 660 – 8010rpm
• Engine speed transient > 15rpm
• Altitude < 8000 ft (2438 m) / Baro > 756mbar
• Fuel level > 5 litres (1.3 US gallons)
• Engine load between 15 – 48% depending on engine speed
Disable Criteria: DFCO enabled (Deceleration Fuel Cut Off)
Monitor: Continuous
Limp home:
• Limit maximum engine speed to 6000 rpm
• Return the fuel system to open loop
• ECU may deactivate two cylinders, the misfiring cylinder and it’s matched other i.e. 1 & 4 or 2 & 3.
Potential failure modes:
• Injector related codes, as these can cause misfire codes to be set.
• VVT or VVL codes set
• Sensor connector and wiring for signs of corrosion or loose connections
• Spark plug / Cylinder compression
• Cam timing / Damage to rocker arm assembly

and

Misfire P1301
P1302
P1301 Misfire level causing emissions increase
P1302 Misfire level causing catalyst system damage
Description
When the engine misfire reaches a high enough percentage the engine emission output levels can exceed the
allowed limits, this will produce the fault code P1301. If the misfire percentage is high enough and there is a
possibility that the catalyst may be damaged then code P1302 will be set.
See misfire faults P0300, P0301, P0302, P0303, P0304
Notes:
• The MIL will flash for a 1302 fault code
• The MIL will be illuminated if the 1301 fault is present for 2 consecutive trips.