P0305 now what?
#1
P0305 now what?
Had my check engine light come on in my 2004 so I checked it out with the scanner and i got a P0305 code. Now I know that it means that a misfire in cylinder 5 was detected, I just want some advice on going about finding out what is causing the misfire before I start buying parts. What should I check first and so forth? I know the 3.0 engines have the infamous issue of the valve seats and Im really hoping I wont have to do any head work and that its something else..
#4
I checked out the Spark Plug Wires from the coil to the actual spark plug and they seem in good shape. I also checked for grounding of spark and that checked out ok as well. I think my next step will be to do a compression test. First it threw out a P0305 and today I drove it around a little bit and it threw out a P0304? What gives?
#5
#6
#7
If you have a known-good coil pack lying around, you could swap it in as a quick n dirty test. If you don't, I'd test the spark with a visual spark tester, make sure it's working or not.
A compression test would come near the end of the diagnostic funnel, as that would be looking for base mechanical reasons for the misfire.
A compression test would come near the end of the diagnostic funnel, as that would be looking for base mechanical reasons for the misfire.
#9
The coil is 3 coils with 2 outputs each. Usually only one side of the coil shorts. I like to take the wire of the missing cylinder and switch it with the wire strait across the coil as they fire together. I watch live missfire data, but you could switch wires, clear codes, then see which missfire code comes back. If the misfire moves to the switched wire cylinder the coil is dirt. If it stays the same missfire code its that plug, wire, injector, or compression. Sounds kind of stupid but it works. Coils fail alot esp. on cars were there in the rear taking alot of heat over a manifold.
#10
#11
The coil is 3 coils with 2 outputs each. Usually only one side of the coil shorts. I like to take the wire of the missing cylinder and switch it with the wire strait across the coil as they fire together. I watch live missfire data, but you could switch wires, clear codes, then see which missfire code comes back. If the misfire moves to the switched wire cylinder the coil is dirt. If it stays the same missfire code its that plug, wire, injector, or compression. Sounds kind of stupid but it works. Coils fail alot esp. on cars were there in the rear taking alot of heat over a manifold.
Take the wire for plug 4. and switch it with the one next to it. like say 5, or 6. at both the plug and the coil. if the misfire moves to whichever plug that is. buy some new wires.
i think its a wire issues. its rare that injectors ever go bad and stop working. and i doubt a compression test will reveal much.
#13
No dont move the wires on the plugs just the missing cylinder strait across the coil. Two plugs fire at the same time on these coil paks so your just changeing which output on the same coil fires which plug. It takes literally seconds if you are watching live missfire data. If you cant watch data then youll have to wait for a code to set.
#14
So I went outside earlier today and did exactly that. Switched the plug straight across on the coil which was cylinder 1 and then ran it a little bit and I got the same code, P0305. I didnt realize it before but I noticed today that it was throwing another code as well P0316. As much as I dont want to admit to it I feel it might be the head issue...
#15
I just ran into the same problem. It can also be the camshaft position sensor and camshaft sequencer. I Had my truck throw a p0304 and a p0316 and fixed both of those and now I'm all good. Check this out. http://www.therangerstation.com/tech...on_sensor.html
#17
#18
#19
#20
http://www.aa1car.com/
Try looking at this, maybe it will help. Save this to your favs. for future references. Good luck. More than likely it's just a bad coil pak.It really shouldn't be that hard to diagnose.
Try looking at this, maybe it will help. Save this to your favs. for future references. Good luck. More than likely it's just a bad coil pak.It really shouldn't be that hard to diagnose.
Last edited by 1kool1; 03-15-2011 at 10:00 PM.
Thread
Thread Starter
Forum
Replies
Last Post