Hello everyone.

I just bought a 2001 Durango (4.7L), and I have some questions about engine specs, and possible issues. I didn't buy this SUV thinking it was cherry, actually I plan on it being a Winter/off road vehicle. With that said I know the truck has some issues, and was hoping someone might be able to help me get a heads up on possible issues before I take it to the mechanic on Monday for maintenance.

First, the engine has 133k miles, and seems to be throwing a random Cyl 5 misfire. the previous owner said they had taken it to multiple Dodge dealerships, and was told it was nothing to worry about. I'm assuming it's probably an old plug, or coil, but I'd like to get a group opinion on what it could be.

Second, the car seems to be having emission issues, but with no code. The scanner I have (Innova 3100i) gives a yellow light (when the misfire code isn't showing), and the manual says it's because the emission systems didn't go into diagnostics. What might be the cause of something like that? The truck doesn't show signs of a major failure. It idles fine, and has power.

Third, I took some screenshots of the Freeze Frame data from the scanner. These pics were taken with the engine warmed up, and parked. Maybe some of these stats would shed light on what could be causing the previous issues, or new ones I haven't noticed yet.

Thank you to any who can help. I really appreciate it.

 

I'd try a new set of copper core plugs for the misfire.

 

Start with a tune up, using OEM plugs as mentioned. Swap the coil to another cylinder to see if it follows or stays with #5.

 

Thanks for the ideas. I do plan on changing the plugs Saturday as well as the oil.

 

Ok, so I discovered something new. The dial on the dash that controls the vents doesn't work. It switches from hot, and cold just fine, but it's stuck blowing air out of the top vent, a little out the center vents, and nadda out of the floor vents. The rear dial seems to work just fine as well, however that has a different issue.

At some point a DVD system was installed. I didn't think anything about it until I moved the rear fan dial to rear controller, and the rear fan went straight to turbo. Looking at it the DVD system is sitting where the rear vent dial should be. Of course I assume the dial was either covered, or removed and not relocated. So my question is, how difficult would it be to require the controller to another location? My repair manual hasn't come in yet, but I assume the dials were just wired connection, and not connected mechanically to anything.

 

Ok, update.

Today I changed all the plugs using the OEM Champion plugs, and made sure to gap them. I check them twice lol. I also replaced the coil on cylinder 5 just to be safe. I deleted the cyl 5 misfire, and took it for a drive. The light didn't come back on for that drive. I visited some family, and on the way back home the light came back on again. Same thing, Cyl 5 misfire. Also the O2s, Cat, and EVA lights are still blinking red.

Any one have any other suggestions?

 

Next update-

Took the truck to a mechanic today, and they did a compression test. They found all the cylinders were doing well except 5. It was pushing 30lbs. They stuck a borescope down the cylinder, and said they can see some burning on the valve. They recommended a cylinder head replacement instead of machining the head as the replacement would be a couple hundred cheaper.

I called another mechanic (Midas), and he said they wanted to replace the whole motor as replacing the head would stress the lower engine.

So question is what should I do? I know a mechanic, and we can replace the head ourself, but is there any truth to the lower engine story?

 

I think midas is trying to sell you an engine.

 

That's what it sounded like to me. What gaskets would I need if I replace the cylinder head? I can buy the cylinder head pre-assembled, but it doesn't have the gaskets.

 

I have no experience with the 4.7, but I'd imagine, other than the head gasket, you'd at least need intake manifold gaskets and possibly exhaust manifold gaskets. Not sure how the timing covers are on that engine. Exhaust manifold bolts might prove to be fun too.