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Discussion Starter · #1 ·
just changed spark plug & coil on plug for cyclinder 2 , also replaced harness for injectors and coils. pulse width for injector #2 is 0 , was thinking compression can be a issue, but just finished taking a 5 hour road trip before the eng light came on . the whole 5 hours no issue - the very next day the engine was studdering .any ideas on what to check ?
 

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1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
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Review your installation for bent connector pins, pinched wiring or loose connections, etc.
Were OEM parts used? The spark plugs should be Champion RER8ZWYCB4 (or 9407).

Swap the #2 plug & coil to an adjacent cylinder and see if the fault carries over to that cylinder instead.

Check the Possible Causes lists for both fault codes to see what they may have in common. Narrow down the list of culprits through diagnosis.

P2305:

80851


P0302:

80852
 

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. . . .just changed spark plug & coil on plug for cyclinder 2 , also replaced harness for injectors and coils. pulse width for injector #2 is 0 , was thinking compression can be a issue, but just finished taking a 5 hour road trip before the eng light came on . the whole 5 hours no issue - the very next day the engine was studdering .any ideas on what to check ? . . . .
Code P2305 means that the PCM has determined there is a problem with the voltage in the secondary circuit associated with coil #2. When the PCM is ready to fire #2 spark plug, it opens the coil driver circuit on the control circuit. The magnetic field generated by the primary circuit collapses and this induces a very high voltage in the secondary circuit and causes an arc / spark plug to fire. This voltage is probably in the range of 30,000 - 40,000 volts or more. This expected secondary high voltage will feed back and induce a lower voltage in the primary coil circuit for a voltage value in the 30 - 50+ volt range. The PCM is NOT seeing this small voltage spike in the primary circuit after the spark plug firing event and sets code P2305 and P0302 cylinder #2 misfire.

Because the PCM has detected a misfire event it is shutting down the driver circuitry to coil #2. Since #2 cylinder is not firing the PCM stops the pulsing of fuel injector #2 so as to not overload the catalytic converter with excess, unburned hydrocarbons and cause it to fail prematurely. That is why you are not seeing an electrical pulse with injector #2.

Did you check the wiring harness for coil control that runs between the PCM (powertrain control module) and the intermediate connector that mates with the wiring harness that runs to the ignition coil? See attached image.

Spark Plug Coil Wiring.gif

Coil #2 control has a DB / TN wire that runs between the PCM and an intermediate connector. At the intermediate connector coil #2 control circuit changes wire color to DB / VT. Check for excessive resistance or short to ground or power on this coil #2 circuit. If you find no problems in the wiring or a problem with pin fitment at the intermediate connector, there could be a problem with mating of the circuit pin to receptacle at the PCM. If the wiring and pin fitment show no issues, then it is possible that the coil #2 driver circuit within the PCM has failed. But condemning the PCM should ONLY be assessed after all other failure possibilities have been investigated.
 

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Discussion Starter · #4 ·
swapped plugs,injector,& coil on plug with another cyclinder. misfire stays on cyclinder 2 , replaced the purge valve for the hell of it but didnt fix it . ive tryed everything i can think of , i briefly looked at the harness and somehow now i have a code for transmission fluid pressure sensor to go along with p0302 & p2305. 2 weeks ago the check eng light would come on & off by itself , now it stays on and wont allow the codes to be erased at all .
 

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. . . . swapped plugs,injector,& coil on plug with another cyclinder. misfire stays on cyclinder 2 , replaced the purge valve for the hell of it but didnt fix it . . . . .
So you have proven that the issue is NOT related to spark plug, coil, or fuel injector. So that leaves a wiring issue between the PCM and coil #2 or a problem with the coil driver #2 PCM. But all avenues of diagnosis must be exhausted before condemning the PCM.

. . . 2 weeks ago the check eng light would come on & off by itself , now it stays on and wont allow the codes to be erased at all . . . .
This is helpful information. With the CHECK ENGINE icon turning on and off intermittently this points to a poor electrical connection somewhere in the wiring harness.

Go back and read my post #3. The PCM is not detecting proper voltage in the secondary coil circuit (high voltage that fires / creates electrical arc at the plug electrode tip). It does this indirectly because a high secondary coil circuit voltage discharge induces a lower voltage in the primary circuit in the range of 30 - 50+ volts.

Check the wiring harness between the PCM, through the intermediate connector, and onto each coil. Each coil has a 2 wire connector. Somewhere in that wiring harness for coil #2 there is more resistance in the primary winding. Higher resistance as compared to the wiring to the other coils is causing a lower secondary voltage buildup in the coil. The PCM detects this lower plug discharge voltage and sets code P2305.

See attached image. Perform resistance checks on #2 coil and other coils for comparison.

Detail Ignition Coil Wiring.gif

How are you attempting to clear the diagnostic codes? Disconnecting the battery for a few seconds will NOT clear codes. That use to be a way to clear codes but Chrysler changed this feature around 2005 - 2008 time frame on vehicles. After that time the only way to clear codes is with a scan tool or fix the code issue and it will reset itself after several successful driving trips.
 

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Discussion Starter · #6 ·
been trying to clear the codes with a ancel x7 scanner - even trying driving it . will be taking a closer look at harness today
 

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. . . .been trying to clear the codes with a ancel x7 scanner - even trying driving it . will be taking a closer look at harness today . . .
You are clearing the codes. But the condition that is causing low voltage on the coil secondary circuit is still present. When you start the engine, the PCM immediately monitors the indirect voltage spike induced on the primary coil circuit that was generated by the firing event on the secondary circuit. So code P2305 is immediately reset.

Is the Ancel X7 scanner a bi-directional scan tool? That means that the tool is able to communicate and activate certain functions within the PCM. Is there a provision for activating the ASD / automatic shut down relay?
 
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