I have a 2003 Ram 1500 4x2 with a 4.7L with 135K miles on it. Thursday night I pulled into the driveway and everything was running fine. The one exception is when I first start the truck to warm it up there was light tapping sound that would go away once the truck runs for a few minutes and warmed up.

I get up to go to work Friday morning and start the truck and it smells like its burning rich. I can smell gas in the exhaust. When I went to back out the of the driveway the truck starts to miss and runs rough. It through a P0300 Code for a random misfire. I pulled the plugs and checked the coil packs. All of the coil packs seemed to be good and tested at 1ohm, I did, however, find that a couple of plugs had gas on them. I ran my ohm meter across all plugs and most were at 5k ohms or less. The two that had gas on them (#6 & #8 cylinder) were are 25K and 30k Ohms.

So I replaced all of the plugs reset my the code and fired up the truck to see how it was behaving. It still ran rough but not as rough as it was in the morning. I added some fuel injector cleaner and went to top it off to see if maybe it was a fuel issue and to see if the CEL came on.

No CEL but it was still running rough. Upon returning to the house the truck started losing power and the CEL came on and threw a P0172 (System Too Rich (Bank1)) and a code for the Cam Shaft sensor. I get to the house and the truck is running real rough. I pop the hood and find that the passenger side valve cover has exploded. ( See picture)

What do you think was the cause of this? Where do I begin? I am pulling the valve cover this morning to inspect for damage. I spent the day trying to find a valve cover and found one. Yay. I will replace the CAM shaft sensor..

What should I check and be looking for? Compression? What else?



Thanks for your help.

 

Probably something under cam came loose...... Pull the valve cover, and see what you find.

 

Well. Here is what I found. I had lifters everywhere, the camshaft was broken in half, and the camshaft bearing cap bolts had broken off the on half of the camshaft. I am missing one of the camshaft bearing cap bolts and can't find it. I have been through the top of the head with a magnet and have found 5 of the 6 bolts. It started raining so I closed the hood and will get back to it when the rain lets up.

Once I find the missing bolt what should my next step be?

Why did the camshaft break in half?

 

Wow. That's pretty wild. Real curious what happened there. Looks like the cam snapped right at one of the bearing journals? Wonder if it lost oil pressure there??

 

Yea that's pretty wild. Not sure if I should replace the camshaft and then check compression or what my next step should be.. any direction would be helpful.

 

Given the catastrophic nature of the failure, and you have no idea what happened there.... I would be real tempted to find a low-mileage used motor, or, if you really like it, long-block it. Then just swap it out, and call it a day....

 

if you have experience with motor work i would recommend heads, pistons, rod bearings and timing chain components. adds up to about 1k in parts by the time your done but it will be like a new motor and not a mystery used motor.

 

The missing bolt is likley what created the hole in the cover.

Looking at the pics it appears there is scoring on the bearing journals. the one next to the break looks pretty severe, my guess is oil starvation, I am not familer with this particular engine, I see what appears to be blue RTV sealant. It does not look like too much was used, but I have seen cases where too much RTV has lead to oil problems due to chunks of the sealant breaking loose, then clogging oil galleries.

I would be suspect of the rest of the engine. If there was starvation this severe here, I wonder what the main bearingss look like. I would pull the engine and go through it top to bottom just for peace of mind, or as others have suggested look for an replacement. Something went very wrong here.

I am sorry for your troubles.

 

As a minimum first-next step, pull the whole head and look under it. You are going to have to rebuilt it or replace it anyways. Pull it, have a looksee, go from there. If you are going the minimalist route, you need to be absolutely certain beyond any doubt that you have found every possible fragment so that the rest of the engine is safe. Find all the pieces, no matter how small, and reconstruct the jigsaw puzzle of parts to know you've got them all. If you cannot get to that confidence level with it in place, then I am with 3rdgens4sell and ajossy. Take it ALL apart, and go from there. To be thorough it would be best to pull the engine and do the work on an engine stand. Not necessarily recommending a full rebuild though. Take it apart, clean things up, and see what you've got. In the end you may end up replacing only a few parts or may be shopping for another engine. Afterwards, at the very least you will be sure there are no unknowns (fragments) that will kill it later.

About the broken cam, yeah that's pretty wild. Plenty to speculate on possible causes but no one can say but you based on what you see after the head is pulled. For examples: a broken/dropped valve, a broken valve spring, a stuck lifter, keeper that let go, a cam chain tensioner fail, a chain jump out of time, a slipped sprocket, a connecting rod let go, plugged oil galleries, so many possibilities ......

Empathetic. Watching this thread now, I am intrigued and curious what is found under the head and what you end up doing with it. Really hoping for you to be able to find the simplest smoothest path of least resistance.

 

Just want to say sorry for your motor.the same whit just happen to me .05 dodge ram 1500 4.7 l. And my 03 Dakota has a blown he'd gasket.I am done with dodges.going back to Chevy...