I have a Porsche Cayenne 2011 3.6, the problem started with a bad coil misfire #5 The car would buckle and eventually the CEL came on. We then replaced the spark plugs and the coil, the problem went away and then came back. We then thought it was a bad fuel injector when the problem got so bad was hard to drive the car because the buckle was so intense. A sound also developed in the engine like a slight clicking. So we went ahead and replaced 3 injector$. The clicking then went away and it CEL was off for about 20 miles and then it came back on again. The car is now buckling slightly and the same code came back misfire #5 code P2312. Now we think it's a short in the harness or a bad coil driver in the ECM?

Has anyone experienced any of these problems?

I'm desperate to find this solution once, Please someone help.

 

"buckle" = bucking?

Codes are:
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P2312 Ignition Coil E Pri Ctrl Circ Low
P2313 Ignition Coil E Pri Ctrl Circ High
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I think some diagnostics are in order. Many ignition systems use a common positive feed to the ignition coil, and switch the ground off and on to fire the coil. Dunno if that's how the 3.6 is wired, but I'll take a quick look at a wiring diagram.

Interesting. A 4 pin coil. Two pins are grounds (#1 and #2) and pin #3 provides +12V to each coil (and is on a fused circuit - one fuse for all the coil power), #4 is the "Actuator" pin - it must switch to ground.

#1 will be BRN/GRN wire (brown with green tracer)
#2 will be BRN (solid brown)
#3 will be RED/GRN (red with a green tracer)
#4 will be GRN/BRN (green with a brown tracer) - this one depends on the coil, this color code is correct for coil #5.

Tests I would do require a voltmeter:

1. Test both grounds. Measure resistance between Pin#1 and the engine block. Measure resistance between Pin#2 and the engine block. Measure resistance between Pin#1 and Pin#2. ALL should be very close to 0.0 Ohms. If different - figure out why.

2. Test power feed to the coil. Measure voltage with ignition switched on, engine not running. Measure between Pin#3 and ground. You should see battery voltage (12V or more.) If not - find out why not. Since these come from a common terminal on the wiring harness the fault would tend to be local to the connector.

3. Test switching circuit. This is trickier. A good O-scope would be useful. This would have to be done with a "back-probe" (a pin type probe that goes in the back of the connector) and while the engine is running. You want to watch it right at startup (since the ECU may turn this circuit off once it realizes the plug isn't firing.) You want to see this pin "go to ground" at about 1/6th engine RPM. That's why the scope. It's hard to see this with a simple meter. If this isn't seen - figure out why. It could be wiring, or it could be the ECU - since that is a cylinder specific output. it goes to Pin#43 on the ECU.

Good luck! Let us know if this is helpful.

That's the diagnostics.

 

So after 6 weeks of siting at the dealer they finally diagnosed that the ECU was bad and replaced it under the California 7-70,000 emissions Warrenty (which is a huge bonus since it would have cost approximately $3,500 to diagnose, install and the parts!!). BUT...now a new problem has shown up - codes P0221 & P0121 which refer to throttle isssues - - the car literally would not accelerate with the gas pedal on the floor and then suddenly work again...

Now the new diagnostics are being send to Porsche america to evaluate. This has Truely been a nightmare and I sure hope it ends soon.

 

Hello , about the throttle isue you can try and do a throttlebody addaption .