P0300 Help!!

[mitsuclipsegsx]

Well I put my car back on the road the other day,(sitting in the garage for 4 months. And hear is the werid part. Im getting a cel for p0300, random misfire, but the car runs great. The cel only comes on when I drive the car for 20-30 min, then the car like boggs and the cel comes on(and when you give it gas it studders). I cleared it 3 times and it takes about 30 min and it happens again, and if I shut the car off for 2 min and start it, its fine. I've searched and I already borrowed a coilpack and power transistor from a buddy and still does it?? What could it be.

 

[EclipticalGS]

this was in another post. its definetaly your front o2 sensor on the o2 housing first, or lastly the crank sensor

 

[mitsuclipsegsx]

Thanks, I'll check the 02. I have a 6 bolt so I dont have the crank sensor anymore.

 

[EclipticalGS]

oO..that explains it..dude that sensor comes on all the time from a 6-bolt swap..sometimes it doesn't..ive had 4 gs-t's and 3/4 had the code, only one was lucky

 

[lazyazzdaddy]

in your profile it says you have dsmlink! just go to "dtc's" and uncheck random misfire then it wont even check for it anymore

 

[mitsuclipsegsx]

I want to know why when I drive my car for 30 min the car studders until I shut the car off? This never happend last year with this motor!

 

[lazyazzdaddy]

When i first bought my car it did that all the time. I had never used dsmlink befor and didn't realize that with the 6 bolt swap that it would throw a random misfire code with out the dtc being set to not scan for that code. did your battery go dead or disconnected when being stored for so long? if so dsmlink would revert back to stock settings unless you reloaded your settings.

 

[mitsuclipsegsx]

I changed my battery and loaded the settings. Well I'll switch the settings today and ill report back.

 

[tenn-gsx]

The skinney of it is that the 2g ecu dont like to see both cam and crank signals coming off of one sensor. The cams advance and retard slightly as they "bounce" on the belt tention. The 2g ecu sees this as a missfire. As a safety the ecu shuts down the injector pulse to the offending cyl so that you dont blow your motor. Just disable the random missfire dtc and your problems will go away. I just delt with this issue last week myself. As far as why it worked fine last year and not this year...... I dont know. But your definately having the random missfire symptoms.