Hey All,

Thanks for taking the time to read this. So! I have a 2003 Ram with the 4.7l and just over 60k now on the clock. Anyway, five or so months a go (about 55k on the clock) the check engine light appeared, a P0301 error, or misfire on Cylinder one. So I reset the code and carried on. At 57k a trip to the local oil & lube store and they mentioned my coolant was low. Filled it up and off I went.

Now, the P0301 code has started to appear more often, not all the time, but after a few hundred miles it flickers on. I decided it was time for new plugs (all the old ones looked fine), also while under the hood the coolant was low again! Argh!

I replaced the plugs, filled the coolant up and just today, after say 300 miles, the coolant was low again. The P0301 code has reared its ugly head again. The truck runs perfect apart from that, the oil looks fine (the level is spot on), there is no white smoke from the exhaust, the coolant temp is a steady 200F. I have noticed that the small overflow pipe attached to the neck of the coolant reservoir looks like its been spitting out some of the coolant.

So I am stumped, anyone have any thoughts? Its hot here, 100F+ during the day, but I am unsure if that extreme heat would cause that much coolant to be lost.

Thanks for the help!

 

Have you drained your oil all together since this started happening? And if so how did it look?

Have you noticed any leakes in the morning? Or any small drips? I know here between the excesive heat and cooler nights that the hoses can sometimes expand and contract and cause a small leak.

For the coolant being low, how low is low? Mine dropps a little but never a really big or noticeable drop.

 

Thanks Truckin....

Well, I haven't drained it yet as it was just changed about, hmmmm, I'd say 500 - 600 miles a go, but yes, that's next on my list. Usually my local lube store lets me know if it looks like there is a problem, however maybe on the last change they did not care. I pulled the dip stick out and the oil looked clean, but I guess that really isn't good enough?

As for how low, well, it was filled right to the top fill level line on the tank, 300 or so miles later, the coolant tank was close to empty this morning

 

I see we are starting to see more and more head gasket issues with the 4.7 on here. Thats scary

 

I would say drain your oil your self and take a look at it to see if it look milky. Also fill up the radaior and park it over a large "CLEAN" carboard box so you can see if anything is dripping or leaking out. On hot asphalt and concrete the coolant doesn't stick around to long but on the box it should leave a nice stain.
Another thing to check would be your heater core, but usually that would flood the cab of the truck if it went out (or at least it did it in the older chevy's).

 

Engine coolant is VERY corrosive and the 4.7, pre '08 anyway, runs the canals in the engine dangerously close to the cylinders. If not a head gasket issue, could be the coolant ate into the cylinder. Common issue.
Because of this, make sure you 4.7 owners change your fluid out more often than the manual calls for. Coolant becomes more corrosive as it loses it's properties...

 

I though coolant was supposed to be NON corrosive?

 

First off engine coolant isn't corrosive is has to many inhibitors in to allow it to corrode. The water that you mix with your coolant may be corrosive but yes as it looses it's properties it can become very corrosive.
On the coolant lost topic, my brother has an '02 4.7l and we have been through 4 radiators and though there are no codes or visible leaks his coolant level drops often. I would have to agree with the hose expansion theory for loss of coolant unless it is leaking into #1 cyl. but i highly doubt that unless you beat your truck like a red headed ford like i do. As for the miss fire, if your plug looks as good as you say it does I'd fluke the coil and check the resistance.

 

I'm not sure if the 03 is the same as my 02 but I had a problem with the plastic coolant resevoir leaking around the nozel. I popped the hood one day after driving for a while and could hear it spewing. I called a Chrystler mechanic friend of mine and asked him if the resevoir was a problem spot and he said it was. I bought a new one for about 55 bucks and installed it. Problem solved. As far as the code I don't have anything for that.

TA

 

When i had my dak I experienced missfires every now and then. Especially if it was raining hard or in the spring when the snow was melting. I chalked it up to moisture getting in the coil packs. Never had the coolant issue. Im sure you would notice if your head gasket was leaking. Milky oil, sweet smell to the exhaust. Thats one heck of alot of coolant to be missing though....