P0300 error code after timing belt change

[agrods]

Hi All,

Just had a service and the timing belt changed on my V6 ML (104,000 km) and the engine light has come on with P0300 code (multiple random misfire). http://engine-codes.com/p0300_mitsubishi.html

The ute is running and idling fine, got mechanic back he looked over it and couldn't find any problems so cleared the code.

4 days later engine light is back on with same code. Got mechanic back again, couldn't find a problem and cleared the code again. He suggested disconnecting the battery overnight??? Doesn't seem like the best solution to me...

He claimed possible dirty fuel was picked up or a coil pack on its way out but car is running perfect. I am very sceptical on the picking up dirty fuel issue as he changed the fuel filter during service, is there a chance he got some crap in the fuel line when changing filter??

My other thought is he hasn't put something back together properly after replacing the timing belt e.g. cable/connector to a sensor or a sensor has been damaged. There looks to be a wire running from the top of the engine down the front of the engine and disappears into the front of the engine, not sure what it does but could it be a source of the issue??

Sorry for long post but a friend is buying the ute from me (I've just picked up my new MQ yeeha) and I can't sell it with an issue, must have too much of a conscience.....

Thanks in advance Agrods.

[agrods]

just a side note, going from the V6 to new diesel...going to take some getting use to...

Agrods

[borngeek]

At least you coming into trouble free motoring with the MQ.

The v6 has been plagued with problems.

Misfire. Check all connection seated

[AnOldFart]

Go back and re-read, the "Possible Causes" listed within your own "link" ....
Just a process of elimination unfortunately. Could be something as simple as a loosely fitted spark plug lead as recently happened to a friend of one of our neighbors who was visiting them after having driven up from Tasmania. He had the vehicle serviced in Tassie just prior to him leaving there and it idled and ran normally driving home from the workshop but, once he got over to the mainland and was traveling at highway speed and attempting to overtake other traffic with his foot held flat to the floor on the accelerator pedal, it would suffer from a severe 'miss' on one cylinder. Long story-short, it turned out to be just the spark plug lead on that cylinder wasn't seated properly during the service....
The other thing worth noting from your own "link" is, Quote: ....When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.
I can't say that it ..is.. for sure but, the "wire running from the top of your engine and disappearing into the front of it" that you've also mentioned in your post could be, the wire going to the CKP Sensor mentioned above.
Obviously it makes sense to concentrate upon the items located close to where the 'actual' work was done during the timing belt replacement and the CKP Sensor and it's wiring would fit that bill. Good luck....
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Update:
Just the simple fact that SoupyCheep has these things listed for sale on their website might give you a bit of a "clue" as to what your "likely" problem might be.....
http://www.ebay.com.au/itm/Tridon-Camsh ... 1806310830
Sounds like it might now be time to get your "mechanic" to hook her up to a "scope" and actually have a "look" at the "quality" of the waveform coming off your vehicle's CKP Sensor....

[agrods]

Thanks guys,
I have read and re read the Possible causes link...checked all spark plug connections and any other electrical connection easily accessible etc.
Engine idles and runs fine which initially lead me away from the CKP but my gut tells me it is an electrical connection. Like you say maybe the CKP in behind the front engine cover.
The apparent misfires must be very very minimal as there is no noticeable loss of power or the feel you get when you drop a cylinder.

Guess I will just keep trying, if anyone has a another idea/solution don't be shy

Thanks Agrods

[AnOldFart]

Thanks guys,
I have read and re read the Possible causes link...checked all spark plug connections and any other electrical connection easily accessible etc.
Engine idles and runs fine which initially lead me away from the CKP but my gut tells me it is an electrical connection. Like you say maybe the CKP in behind the front engine cover.
The apparent misfires must be very very minimal as there is no noticeable loss of power or the feel you get when you drop a cylinder.
Guess I will just keep trying, if anyone has a another idea/solution don't be shy
Thanks Agrods

Lack of any "actual" noticeable "miss" or poor engine performance points even more, to it being just a "sensor fault". Have a look at the contents of the "link" in my 'update' to my previous comments above....

[hvac guy]

Check the timing from tdc from piston number one

[greyghost08]

hi I have same problem after timing belt change back to mechanics to c what problem is

[Big Brad]

Done my belt 3 times now at 340 000 klm on the old Ml V6.

Never had a problem so definitely a miss by the mechanic i would say