540i misfiring :( (P0306, P0308 and P0300)

[PRO®]

After warming up my car this morning, I received a CEL due to a Cylinder 6 and Cylinder 8 misfire.

The codes thrown were P0306, P0308 and two P0300 codes for the random misfire.

Also, would it be harmful to drive the car while the codes are present? The car sounds like its running fine, I warmed up the car and didn't notice the CEL til I came back to the car and hopped in.

Would a bad cat cause these codes?

Autozone(lol) "says"

probable causes include

a. plugged or faulty fuel injectors
b. vacuum leak
c. engine mechanical condition.

maybe i simply need a tune up? hmm

[Got Milk?]

My buddys car was misfiring, but it stopped and then the next day the check engine light came on, and its for the cat.

[CaTcH22]

Does it have coil packs or wires? If you washed the motor, water will get down near the plugs and short out the coils. If it doesnt have coils....prolly tune up.

[Elbow]

Now the fun begins...sorry. :(

[CaTcH22]

Edit: I just saw your other post about your radiator hose. Did it bust and spray coolant everywhere? Did the car happen to overheat?

[Logan]

Most likely a vacuum leak. Trace EVERY line from the intake manifold.

[Barefoot]

Now the fun begins...sorry. :(

thats what im saying.

[95alty]

Get that tune up... and if its not that- Welcome to the bimmer world

[crashtke]

When is the last time the plugs were changed? Have you tried playing with the coil packs. Not sure on the BMW's, but on other motors you can try swapping coil packs and see if the misfire follows a particular coil pack.

[PRO®]

Edit: I just saw your other post about your radiator hose. Did it bust and spray coolant everywhere? Did the car happen to overheat?

it didnt overheat, i changed the hose out because it was swelling. when i changed out the hose, coolant did come out, but not spray everywhere, it just poured slowly down.


Now the fun begins...sorry. :(

Get that tune up... and if its not that- Welcome to the bimmer world

:(


When is the last time the plugs were changed? Have you tried playing with the coil packs. Not sure on the BMW's, but on other motors you can try swapping coil packs and see if the misfire follows a particular coil pack.


Most likely a vacuum leak. Trace EVERY line from the intake manifold.

http://i78.photobucket.com/albums/j113/staysikwitit/2010-04-10201737.jpg


okay for those wondering, no thats not a mushroom its an arrow, lol. I just looked over all the hoses and noticed that that hose was a little(meaning like 2mm out)pushed out,it was in, but not pushed in all the way. perhaps when changing out the radiator hose I nudged it out some.

could that possibly cause those codes?