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P0307

Tmiller72

Full Member
Joined
Jun 10, 2007
Messages
37
Location
Boone, NC
I had posted a problem I was having a couple of months ago.  Check engine light comes on when I get to 60-70mph.  I had the plugs and wires replaced back then, but I'm still getting the same error.  I had the code read today and got the same Cylinder 7 missfire P0307.  Any ideas what it could be??  2002 2500 8.1L  87,000 miles.  Thanks!!!
 
I would consider the coil for that cylinder and if not there I would have the dealer check it out for you. The coils are easy enough to change, so maybe you could try switching with another to see if the problems moves with the coil.
 
A vote for cat.  Sadly, you're out of warranty on it.
 
Tmiller72 said:
Is it pricey to replace the cat??

Oh yeah.

On the 5.3, for example, it's an assembly - y-pipe with both cats, that assembly is well over $600.

Now, you could use a non-stock replacement and cut out the factory one.  The passenger side is easier, unfortunately you have the issue with the driver's side.
 
Called the dealer and mentioned all the above suggestions.  As far as the cat goes, he said if that was the problem then I should be getting missfires in multiple cylinders.  He did mention that it could be the coils and suggested switching them to see if that was the problem.  I'd like to fix this as cheap as possible.  I'm thinking of getting a new truck and would rather sell it than trade it in.  But obviously can't sell it to someone if there is a problem with it.  Trading it is a different story since the dealer can fix it themselves.  I just don't need all the power that the 2500 has.  I live in the mountains and it burns wayyyy too much gas.
 
My bad cat started with just a P0307 for a while before it began multiple cylinders (P0300).  Don't trust your dealer :)
 
I've spent too much money on this truck lately.  I'd love to get rid of it.  New tires, new brakes, new crankshaft position sensor, new plugs and I still need to replace the right rear cladding ($160). 
 
Another tally for a plugged cat. If you don't have emissions testing... you could remove that pipe and, um... clean out the cats...

I am in no way suggesting that you run without cats. But you would fix that issue...
 
Finally took the truck in on Wed.  Dealer did a major fuel system cleaning and replaced an almost totally clogged fuel filter.  Also had an oil change.  I was there almost 7 hours.  Drove the truck home, no check engine light.  Yes!  The next day (yesterday) the CEL came on again.  No!  Today it came on a bunch of times.  I'm so mad.  All I want is to get this thing fixed so I can sell it and get a newer Av.  No need for a 2500 anymore.  But I can't sell it with a CEL flashing.  Guess I'll be going back to the dealer next week.  I paid about $230 for the work that was done to fix the problem according to them.  What responsiblity does the dealer have to me to fix the problem since I have already paid.  Can I be expected to continue to pay for each time they claim to fix it?
 
Tmiller72 said:
Finally took the truck in on Wed.  Dealer did a major fuel system cleaning and replaced an almost totally clogged fuel filter.  Also had an oil change.  I was there almost 7 hours.  Drove the truck home, no check engine light.  Yes!  The next day (yesterday) the CEL came on again.  No!  Today it came on a bunch of times.  I'm so mad.  All I want is to get this thing fixed so I can sell it and get a newer Av.  No need for a 2500 anymore.  But I can't sell it with a CEL flashing.  Guess I'll be going back to the dealer next week.  I paid about $230 for the work that was done to fix the problem according to them.  What responsiblity does the dealer have to me to fix the problem since I have already paid.  Can I be expected to continue to pay for each time they claim to fix it?
they're going to say those things needed to be done anyway, so unfortunately you will have to keep on paying, can't hurt to try and work out some kind of deal on future repairs though 

good luck
 
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