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P0305 code

Cibargar69

New member
OK. I'll try and be quick. I have a 2000GP GT3.8 / 235,000 miles

I have been receiving an intermittent p0305 code. Car absolutely misses...more pronounced under acceleration.

Faulty spark plug or wire--->REPLACED :th_thumb-up:
Faulty coil (pack) ---> REPLACED :th_thumb-up:
Faulty oxygen sensor(s) ---> REPLACED A FEW LAST YEAR :th_thumb-up:
Faulty fuel injector --->:th_scratchhead:
Burned exhaust valve ---> :th_scratchhead:
Faulty catalytic converter(s) ---> REPLACED LAST YEAR
Running out of fuel ---> NEVER
Poor compression ---> UNKNOWN
Defective computer --->ICM REPLACED :th_thumb-up:

Does anyone have similar experiences or ideas?
 


The thing that bothers me is the problem is intermittent. When idiot light goes off (cause it does), and I don't heavy accelerate, car seems fine and light goes off after some time. But I can fore a failure frequently by heaving accelerating...which is leaning me to an injector but I'll plead ignorance...
 
Are you loosing any coolant? The plenum could be starting to leak coolant internally. I agree with fivefingerdeathpunch, if you suspect the injector and don't have a way to test it, swap it with #3. While you are at it swap the plug and wire with other cylinders to make sure they are good. New does not always mean good. The valves do not normally have problems on these engines.
 


OK...I kinda embarrassed (and quite pissed)...but after changing plugs / wires / ICM and coil, it was realized that coil/plug connection were incorrectly installed. 2 and 5 as well as 1 and 6 were swapped. This must have happened when my wife had the car and was staying for long duration at a hotel. She had begun feeling a loss of power months ago, but there was no visible indication of a problem until recently. After correcting coil/plug connections and adding some electro grease to the coil connections, all is as it should be. Wifey is now aware that doors must be locked at all times...
 
Wonderful. So there is a bandit swapping the coil packs? lol they are the same but the numbers are different they can be swapped if the wires go to the correct destination (but it's easy enough to switch as you know) Similar thing happened to me on a 3400 rebuild; I left the coil packs installed as they were when I got the car and only matched the numbers-misfire but it is what it is.
 
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The packs were off or the plugs were?

I don't think coil pack placement really matters.

Someone broke into your car and swapped them? Lmao
 
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