P0300

[FLAMSP]

I did a search, found out that it could be a number of things, also found that many of the threads were left open-ended. Now that I am stuck trying to solve this CEL, do you know, or know of anyone, that has successfully solved this issue?

 

[Spiced MSP]

I believe that is the random misfire code??? replacing the coil packs and wires fixed it for me.

 

[BOOSTR]

P300 can be caused by many things but not limited to:
a vacuum leak in the intake manifold
throttle body or vacuum plumbing,
EGR valve that is leaking exhaust into the intake manifold
PCV valve that is leaking
even bad gasoline.

Less common causes include bad spark plug wires, worn or fouled spark plugs, a weak ignition coil, dirty fuel injectors, low fuel pressure, or weak valve springs.

What's your VAC reading at idle and what does the idle do while the engine is running?

 

[FLAMSP]

Vacume at ilde is 19-21, 22 on downshift. Happened today, for the first time, while going into 5th @ 57 mph. Car felt really bogged down, hard to keep it going, and rpm dipped pretty hard with a flashing cel. Then i parked for fourty mins or so, started the car with no problems, drove with no problems, cel remains on.

 

[JCell]

a flashing cel means it very serious alex...


take iy easy until u get it fixed

 

[StealthWyvern]

I believe that is the random misfire code??? replacing the coil packs and wires fixed it for me.

bingo, it is a random mis code... like you already stated its generally coil packs or wires that cause this. replace them and he should be golden.

 

[TWISFM]

i think you popped vTACH

 

[sandspeed]

i think you popped vTACH

baaaaaaaaaaa

alex, i've got some extra coil packs you can use to try get rid of the cel. There old but you never know.

 

[FLAMSP]

a flashing cel means it very serious alex...


take iy easy until u get it fixed

no longer flashes, but it did for a bit.

 

[FLAMSP]

baaaaaaaaaaa

alex, i've got some extra coil packs you can use to try get rid of the cel. There old but you never know.

thank you, i'll pm you if needed

 

[BOOSTR]

Your vac readings are within spec, so rule out a leak. The flashing cel just reflects the cylinder misfires and is really only a concern if you are still using your cat pipe, as you can ruin them running the engine.

I'd check the plugs, pcv and replace both if its been a while or you never have. Give the older coil packs a try as well. But depending on your mileage, the oem coil packs should still be hanging in there.

Cel will stay on until you fix the problem, complete the drive cycle (30 miles or so) or clear it.

 

[JCell]

vac readings will be in check even with a vac leak

it depends on where the leak is.... and where the map is hooked up

 

[FLAMSP]

Just checked the plugs, everything is in order, gap was fine, electrode was fine. Is there a way to test the coil packs? I know you can check the wires with a multimeter, but can the coil packs be tested? Also, I cleaned just about every eletrical connention on the car, just to make sure it wasnt dirty connections causing the misfire, and cleared the CEL (reset pcm).

 

[FLAMSP]

more info

77k on the car
PCV is good, but I never changed it, got the car three years ago
EGRv never been cleaned, just seafoamed, but i have a feeling this may be my problem.

 

[JCell]

PCV is like 10 bucks... change it

me and ian have told you already to clean our egr, there is no way seafoam got to that area

get to it

 

[FLAMSP]

yes sir!
thanks for the help J

 

[FLAMSP]

anyone have the part # for the millenia pcv? is it for the 2.5 supercharged?

 

[BOOSTR]

I use the Purolator PV1047 which you can get at Advanced. I change mine a lot more than you do. Also use Seafoam and have never cleaned my EGR nor will I. Have 80K miles and the oem coil packs and wires. Change my plugs about as often as the pcv.

 

[boostfreak]

Purolator PV1047
what is that?? sorry just would like to know. thanks!

 

[FLAMSP]

ok got the millenia pcv, car runs well, like nothing ever happend... not sure what to think?