2002 dodge dakota p0305 code - misfire

Joined
Nov 12, 2003
Messages
37
Location
Colorado Springs
My 2002 dodge dakota 4x4 has 168k miles on it, and recently it runs rough for ~30 seconds after a cold start. This problem has gotten progressively worse, and issued a p0305 code last night after it ran very rough right after it was started. The code means that there is a misfire on cylinder 5. The power seems good, and doesn't seem to have this issue when it is warm. After about the first 30 seconds to a minute, it seems to idle and run very smoothly. It doesn't do this every time it is started either. Since it was about time to change the spark plugs, I changed those and the ignition coils a few weeks ago. This did not fix the problem. Do you have any idea what this might be? From searching on the Internet, it could be a fuel injector, O2 sensor, PCM, or a bad valve or piston. Some of these seem unlikely since this only seems to happen after a cold start. If an O2 sensor were bad, wouldn't this result in another or different code? Might this be a fuel pump issue?
 
Joined
Mar 1, 2007
Messages
1,768
Location
NE
Swap injectors, do a compression or leak down test and check the fuel pressure at the rail. What engine?
 
Joined
Feb 1, 2009
Messages
8,859
Location
Texas
What engine? Is there an audible "ticking" when its running rough? Is the "rough running" a random shaking/sputtering affecting all cylinders, or is it a rhythmic thumping like a single dead cylinder? Obviously cyl 5 is a suspect, but it could also be that it just happened to be the one that misfired enough to cross the trouble-code threshold.
 
Last edited:

Gilberttribe

Thread starter
Joined
Nov 12, 2003
Messages
37
Location
Colorado Springs
I forgot to mention it has a 4.7L engine. I do have a small coolant leak, but that is a radiator issue with a very small external leak. I haven't had a UOA done recently, but I don't see any other evidence that this is a head gasket leak.
 
Last edited:
Joined
Oct 10, 2008
Messages
19,699
Location
Sunny Florida
Originally Posted By: VNTS
Swap injectors, do a compression or leak down test and check the fuel pressure at the rail. What engine?
Excellent advice. As long as the plugs, wires, coils are all good this has to be the issue. swapping injectors is usually pretty easy...
 
Joined
Feb 1, 2009
Messages
8,859
Location
Texas
I'd check fuel pressure before I dug in any deeper. If the fuel pump is "lazy" when its cold, it could run rough. It wouldn't be a dead-hole kind of thump, it would just be roughness. A different cylinder might set a code different times. That's why I asked about what kind of "rough running" it is. If its a dead miss, its not the fuel pressure and could be an injector. If its a random misfire, it could be fuel pressure. Early 4.7s sometimes throw their cam followers off, too(*), but that doesn't usually fix itself. A slow-filling or sludgy lash adjuster could cause reduced valve lift on one hole, and that might be enough to set a misfire code too, but it would be accompanied by the audible ticking sound. (*)-the prevailing theory is that the hydraulic lash adjusters get sticky, then when you shut the engine down the adjusters on the valves that land on the peak of the lobe bleed down. When you start it up, the follower is very loose and bounces around until the oil pressure pumps up the follower and sometimes the follower pops out. You can pop them right back in, and some people even put washers under the lash adjusters to prevent them from collapsing all the way. Good videos on popping rocker arms back on and fixing up the lash adjusters here: http://www.youtube.com/watch?v=ksrDE2zjC34 http://www.youtube.com/watch?v=st1AoYfTPlY http://www.youtube.com/watch?v=kjtSStaNfPI But the moral is use good oil, a filter with a good ADBV, and there's good reason to use Xw20 as recommended in these engines (faster pressure buildup).
 

Gilberttribe

Thread starter
Joined
Nov 12, 2003
Messages
37
Location
Colorado Springs
Thank you for all the great advice. I'll start with the suggestions here, and update here as I progress. This problem doesn't happen every time it is cold nor does it throw a code when it does start rough. I didn't notice a rhythmic pattern to the rough idle, and it is pretty rough as it shakes the entire pickup. Even my son who didn't notice catching the side of garage door opening with the side of the car would notice this. Last night was the first time it had issued a code after I started it. I haven't noticed any ticking, but I will listen for that as well as see if there is a pattern to the rough idle.
 

Gilberttribe

Thread starter
Joined
Nov 12, 2003
Messages
37
Location
Colorado Springs
I replaced the injector for cylinder 5, and removed the code. This morning the pickup started up with no issues, but I'll have to see how things go over the next several days. I did notice that there is a slight tick that I can only hear when the hood is open, so I'll monitor that as well. As usual, when replacing the injector, I went through the three questions I often ask myself when working on our vehicles. 1. How do I get to that? 2. Where did I just put that? 3. Where did I just drop that? Last night went better than usual, so I only spent about 1/4 of time pulling a clip out of a little crevice that I dropped it in.
 

Gilberttribe

Thread starter
Joined
Nov 12, 2003
Messages
37
Location
Colorado Springs
If this doesn't work, I'll get a fuel pressure gauge. The parts store I went to didn't have one for loan, and the gauge was twice as much as the injector. The old injector had a rubber or plastic insert in the injector cavity, but the new one didn't. The new one seems to work Ok, but is that unusual? The old injector also had a little sludge around where the fuel rail connects to the injector. Is that normal?
 
Joined
Feb 15, 2007
Messages
2,081
Location
Los Angeles, California
Originally Posted By: Gilberttribe
I forgot to mention it has a 4.7L engine. I do have a small coolant leak, but that is a radiator issue with a very small external leak. I haven't had a UOA done recently, but I don't see any other evidence that this is a head gasket leak.
Gilberttribe, I fairly recently got rid of my 01' Durango with the same engine as you have. I'm much afraid you may have to have your main computer swaped out! I got the same codes as you mentioned and replaced the ejectors, coil packs and more and still on ocassion would get a rough idle that couldn't get pinned down. What might help you is try and get your battery checked and recharged as rumors are that Dodge brand cars/trucks need a fully charged/strong battery. Since that is the most cost effective method to try I'd go for that first and perhaps a bottle of strong ejector cleaner and take it out on the freeway and see what happens. On my Durango the code would reset-itself after a time. Good luck with your Dakota as if you really love your truck then it's always worth it to repair it. It's just my pocket book got tapped out before really solving my problem. Durango
 

Gilberttribe

Thread starter
Joined
Nov 12, 2003
Messages
37
Location
Colorado Springs
Thank you for your reply. Since my post a few weeks ago, I just got the same error code again on the same cylinder. Replacing the spark plugs, coil packs, and that particular injector has not corrected the problem. I'll check the battery, and possibly look into replacing the computer. I see I can get a PCM online that is supposedly programmed for my VIN. I've not looked into this much, so I'll need to do some more research to see if the online PCM is a legitimate option. I also just got an inexpensive Bluetooth ODB reader, so I'm going to see if that provides any useful information. If I loved working on cars, I'd be loving my Dakota right now because I'm smelling a slight hint of anitfreeze in the cab.
 
Joined
Aug 21, 2013
Messages
4,276
Location
Central Maryland
Good point about the battery. My '01 3.9L got really bizarre right before it needed a new battery. The 4.7L is not a bad engine, but like all iron/aluminum combinations can suffer head gasket problems, after an overheat or just from age.
 
Joined
Oct 10, 2008
Messages
19,699
Location
Sunny Florida
Originally Posted By: HangFire
Good point about the battery. My '01 3.9L got really bizarre right before it needed a new battery. The 4.7L is not a bad engine, but like all iron/aluminum combinations can suffer head gasket problems, after an overheat or just from age.
Head gasket issues in iron block/aluminum head engines for domestic automakers virtually disappeared years ago. How long were you away?
 
Joined
Aug 21, 2013
Messages
4,276
Location
Central Maryland
Originally Posted By: SteveSRT8
Originally Posted By: HangFire
Good point about the battery. My '01 3.9L got really bizarre right before it needed a new battery. The 4.7L is not a bad engine, but like all iron/aluminum combinations can suffer head gasket problems, after an overheat or just from age.
Head gasket issues in iron block/aluminum head engines for domestic automakers virtually disappeared years ago. How long were you away?
Hmm. Come hang out in Dakota forums for a while. As they age, high mileage 4.7's have much more head gasket problems than the older/larger iron block/head engine designs sold concurrently. For most of the original owners, their 4.7's lasted long enough that it didn't matter. Like I said, it takes an overheat or substantial aging to show up. But it happens.
 
Joined
Oct 10, 2008
Messages
19,699
Location
Sunny Florida
Originally Posted By: HangFire
Originally Posted By: SteveSRT8
Originally Posted By: HangFire
Good point about the battery. My '01 3.9L got really bizarre right before it needed a new battery. The 4.7L is not a bad engine, but like all iron/aluminum combinations can suffer head gasket problems, after an overheat or just from age.
Head gasket issues in iron block/aluminum head engines for domestic automakers virtually disappeared years ago. How long were you away?
Hmm. Come hang out in Dakota forums for a while. As they age, high mileage 4.7's have much more head gasket problems than the older/larger iron block/head engine designs sold concurrently. For most of the original owners, their 4.7's lasted long enough that it didn't matter. Like I said, it takes an overheat or substantial aging to show up. But it happens.
Beware of Internet Amplification. With over 15 million built it is highly likely a small percentage will experience some sort of failure. A few hundred would likely FILL a forum with complaints!
 
Joined
Aug 21, 2013
Messages
4,276
Location
Central Maryland
Originally Posted By: SteveSRT8
Beware of Internet Amplification. With over 15 million built it is highly likely a small percentage will experience some sort of failure. A few hundred would likely FILL a forum with complaints!
Uh... it's not like I'm sounding some huge alarm bell here. I'm not posting about 4.7L problems in every thread possible. He has a 4.7L. It has problems. Head gasket failures happen in all engines, including 4.7L's. It deserves looking into. Other folks have had that problem, a few more than the 314/360 based engines. That's all. I've had iron/iron engines fail head gaskets, including the vaunted 3.0L Vulcan. I only brought up Dakota forums because you seemed to think that it just wasn't possible that 4.7's have a higher HG failure rate. It's not Ford 3.8L V6 level HG issues, but it happens.
 
Joined
Sep 23, 2007
Messages
8,598
Location
Florida
Originally Posted By: SteveSRT8
Originally Posted By: HangFire
Good point about the battery. My '01 3.9L got really bizarre right before it needed a new battery. The 4.7L is not a bad engine, but like all iron/aluminum combinations can suffer head gasket problems, after an overheat or just from age.
Head gasket issues in iron block/aluminum head engines for domestic automakers virtually disappeared years ago. How long were you away?
Virtually gone? The GM 3.5 OHV is not much better in that respect when compared to the 3400, 3100, and 2.8 V6 Aluminum heads on iron blocks do not cause head gasket failure, bad engine designs do.
 
Joined
Oct 10, 2008
Messages
19,699
Location
Sunny Florida
Originally Posted By: artificialist
Originally Posted By: SteveSRT8
Originally Posted By: HangFire
Good point about the battery. My '01 3.9L got really bizarre right before it needed a new battery. The 4.7L is not a bad engine, but like all iron/aluminum combinations can suffer head gasket problems, after an overheat or just from age.
Head gasket issues in iron block/aluminum head engines for domestic automakers virtually disappeared years ago. How long were you away?
Virtually gone? The GM 3.5 OHV is not much better in that respect when compared to the 3400, 3100, and 2.8 V6 Aluminum heads on iron blocks do not cause head gasket failure, bad engine designs do.
Completely agreed. Please provide your personal idea of what is an acceptable failure rate. Personally, in a mass produced car with decent volume, I feel that .1% is acceptable. At the volume of that 4.7 that yields 15000 engines. That will burn the Net for years...
 
Top