WTF!?! Random misfire happening around 3k RPMs at 71-74 MPH in 5th gear only.

[death1969]

hmmm... i had the same thing happen, most of the time my cel was not on but i checked with my obd2 reader and found that i had that a P0300 i cleared it an have had not issues.. no clue

[evosoh]

It is definitely a misfire. This is shown from your AFR going lean. You could check if your cam sensors are faulty. Why not disconnect the knock sensor to see if the problem goes away.

Originally Posted by darkside4G63

i am having the exact same problem as the OP. i have replaced the plugs (several times actually), i got the Spark Tech non cdi COP so my coils are replaced, and i had the 2 vacuum lines pop off the EGR and i put them back on and zip tied them up. i cleared the codes and it stopped for a while (2000 mi.) then it happened again. i checked and the vacuum hoses are still good. i noticed that i was picking up crazy knock when it happens and my wideband bottoms out lean. i dont think it is a fuel issue. im leaning more towards that phantom knock coming from the drivetrain via the input shaft. has anyone had any luck altering the knock filters in ECU Flash in the 3000 rpm, low load area to fix this. if so what direction do you go with the values to de-sensitze the knock sensor? Tephra, do you have any input? any help would be greatly appreceiated as i do not have the funds to rebuild my tranny at this time.

[mt057]

If you are throwing a p0300 and drive an Evo 8. You should check out the p0300 disable test. It will get rid of the shuttering that happens on the highway related to the p0300.

Changing periphery bit 2 to e7cf will stop it I believe, but I recommend reading the thread it is very informative if you have not already.

disable P0300 test