Dodge Mechanic

[dragos13]

I have a 1996 Dodge Ram 1500 that had the check engine light on. Went to the dealer and have 4 DTC's as listed below:

P0300- Multi Cyl Misfire
P0301- Cyl #1 Misfire 82 SSS
P0302- Cyl #2 Misfire 110 SSS
P0303- Cyl #3 Misfire 82 SSS

Now, I'm no mechanic but it seems these are related. I was wondering if anyone has any advice, suggestions, connections, etc. I was thinking maybe its a head gasket causing low compression so it doesn't fire? They also say the motor is burning oil. Plugs, wires, cap, and rotor have all been replaced this year. Please let me know if anyone can help. Huge thanks in advance!

[T Baggins]

I have a simple explanation for this: It' a Dodge.

Next time, buy a Ford.

Also, FWIW, you can go to checker and they'll plug in and pull the codes for you no-charge.

Not sure if we have any Dodge mech's in the hizzle...

[Aracheon]

Pffft... you got it backwards, T Bag... Dodge > Ford. ;)


Casey, give my brother Cory a call... tell him I sent you. (1-877-879-3437)

[dragos13]

Thanks Chris, I'll hit him up later this week!

[benfoxmra95]

its not a head gasket because cylinders 1,2,3 are not all on the same side, 1,3 are on one side, and cylinder 2 is on the other.

Rule out the head gasket.

You might check for and intake manifold gasket leak.

But more than likely it's the ignition coil. throw a new one on it, they are cheap, you could even try one from a junk yard for like $20, just for diagnosis sake.

When a 96 newer vehicle sets a misfire code, it's electrically related, I.E. plugs, cap and rotor, coil.

the computer has no way figuring out the engine has low compression in individual cylinders, or the engine is using oil or coolant. it would have to be using enough oil and coolant to blow the spark completey out, and if it was you'd see a shit ton of blue or white smoke out the exhaust.

Check the plugs closely for carbon tracks, or just replace them they are cheap.

You should also check the injector connections make sure they are plugged in and firing the injectors.

If you have a scanner, hook it up and monitor the LTFT's on both banks, and if you can report that info back to me that will tell me a whole lot, and I could probably tell you exactly what was happening.

Positive LTFT's mean the computer is adding fuel, Negative LTFT's mean it's removing fuel.

So let's say your bank 1 side (cylinders 1,3,5,7) have a LTFT of +25 and bank 2 (cylinders 2,4,6,8.) have a LTFT of -7, this means the computer is adding fuel to bank 1 becuase it's seeing a lean condition on that side of the motor in the account of there being no spark in those cylinders.

o2 sensors read oxygen content! not Fuel content!!!!, so when a cylinder has no spark there's more air being added to the exhaust system and the o2's read lean, then the computer starts adding fuel to compensate....

Everyone gets tripped up on this because they think that an o2 sensor read fuel content....it does not!

A dribbling injector will cause an overly rich condition and your LTFT's will go negative trying to cut down fuel to that side and will cause some cylidners to run too lean and the dribbling one will be rich. this scenario is hard to diagnose properly becuase, there's only one o2 sensor on each side of the motor so you don't know what each individual cylinder is doing.

Again, I'd really be looking into all the electrical sides of the issue. Like I said earlier, the computer has no way of determining a missfire from mechanical faults....You'll see smoke way before the computer even can think about setting a missfire code.

[dragos13]

Ben, thanks alot for the great response. The truck doesn't smoke and I never really noticed it getting low on oil, that was just the dealers diagnostic that it was burning. I never have to top it off between oil changes.

First thing I'll do is replace the ignition coil. The cap, plugs, wires, and rotor have been replaced recently. I'll throw in new plugs again while I'm at it also.

Last, what type of scanner do I need to monitor the LTFT's? I am not too familiar with trucks so sorry if I sound like an idiot. Also, since the check engine light is now off, and the truck "feels" fine, after I change the ignition coil can I test something? Or just wait for the trouble to return or stay away? Let me know. I appreciate all the help with this.

[dragos13]

I changed out the ignition coil as Ben stated and the problem seemed to go away. Everything was running fine for about 3 months and now has returned. I got the check engine light on and the codes again are showing misfire. Same codes as above. Got any ideas?

[Ray-Ray]

I changed out the ignition coil as Ben stated and the problem seemed to go away. Everything was running fine for about 3 months and now has returned. I got the check engine light on and the codes again are showing misfire. Same codes as above. Got any ideas?

Buy a FORD!

[polar x]

Check the harness for rubbing issues. Maybe its grounding out on the motor. :?:

[dragos13]

Ray-Ray I will take that into consideration (yeah right)

Chris, let me look around as that could make sense. The problem cleared after replacing the coil for about 3 months. Maybe I moved some wires around, got lucky, and now they are grounding again. I'll check that out tonight.

Thanks everyone. If anyone else has ideas or suggestions let me know!

[cromer611]

my jeep did the same thing. the codes said misfiring on a few cylinders. I asked my bro in law(the one who did the service on it) and he said he forgot to gap a few of the spark plugs.

sure enough i pull them and the #6 plug had like 0mm of gap. SOB dropped the plug on the electrode : P

anyway i gaped them and it doesnt misfire.

[T Baggins]

my jeep did the same thing. the codes said misfiring on a few cylinders. I asked my bro in law(the one who did the service on it) and he said he forgot to gap a few of the spark plugs.

sure enough i pull them and the #6 plug had like 0mm of gap. SOB dropped the plug on the electrode : P

anyway i gaped them and it doesnt misfire.

You "gaped" them?!!??

http://www.urbandictionary.com/define.php?term=gaped

Poor sparkplugs... what did they ever do to you?

[Hotrod]

OMG! Tony, that was brilliant! :D