Not looking good...

[TheJackal]

I'll start the story from the beginning.

Ever since my dad gave me the Ex at 100,000, it had a slight coolant leak that I've never been able to pinpoint. I had hoped that the leak had been external; as there seems to be a gradual "ooze" of stuff that leaks from the engine over time. Oil also seems to seep out slightly, but not enough to be noticeable.

Around the beginning of summer, I was headed down the Interstate and suddenly the engine starts shaking, and Check Engine is lit. Code P0304--Misfire in Cylinder #4. I ended up going to the dealer to have the plugs changed as nothing I have would reach, and didn't have any time to fool around that week. I should've asked to see the old plugs, but I didn't think of it when I went to pick it up.

So the plugs and wires were changed and life went back to normal. Or so, I hoped. That optimism changed over the past week, and yesterday particularly when I started the engine. It started shaking again, CEL on. This time, the shaking seems to go away, especially under acceleration. At first I thought it was an idle issue, but later seemed to do it while driving as well.

Today, I have the DTCs pulled at Autozone. P0304. ****.

I'm sure you can put 2 and 2 together now. Especially since it seems to correlate to me making sure the radiator stays full over the summer.

The thing that makes this a total bummer for me tho is I don't technically own the car; my folks still own it and they were planning to give it to me. Unfortunately, they've been pushing me pretty hard to buy something new, because to them new=better. I'd like to just fix the issue and go on, but I know when they find out about this, it's going to be the end of the line for the Explorer.

(sorry to **** on everyone's parade this morning, but I feel pretty crappy about this right now.)

 

[IZwack]

Pulling the heads technically isnt that difficult - it just takes time. So I'd probably set aside a few days in the future, label everything you remove, pull the head and see whats up - maybe its just a gasket that needs to be replaced.

 

[marragtop]

I think before pulling heads, you should do some more testing. Check the wires and make sure they are on properly. Consider changing #4 wire with another wire and see if the problem moves to the other cylinder. Check for vacuum leaks. Consider doing a leak down test also.

 

[TheJackal]

Looks like it may not be the head gasket as I originally suspected. I did some research on the site and found a couple of people with gradual fouling of #4 like I had, and it turns out to be the lower intake gasket.

For a temporary solution I thought I'd try this Bar's Leaks stuff, but so far it doesn't appear to do anything. In fact, it looks like more coolant has leaked out now. Later on I learned there was something better to use but too late now.

I took out the #4 plug and sprayed it down well with carb cleaner. Engine misfired for a bit after starting, but then cleared up quickly.

so just in case anyone was wondering about this, if you've got repeated fouling of #4, it could be the lower intake gasket. :exp:

 

[marragtop]

If the miss clears up as the engine warms up it could be the intake gasket. As the metal warms, it will expand and reduce the vacuum leak.

Also, I'd flush the Barrs leak out of the system asap. My experience is that it will do more harm than good. I suspect that comment will generate additional discussion!!

 

[Joe Dirt]

Yeah, I've never been a fan of that stuff. I've always err'd on the side of just replacing the gasket in question.

 

[TheJackal]

If the miss clears up as the engine warms up it could be the intake gasket. As the metal warms, it will expand and reduce the vacuum leak.

Yeah, it was doing that. Looks like it's gasket time.

Also, I'd flush the Barrs leak out of the system asap. My experience is that it will do more harm than good. I suspect that comment will generate additional discussion!!

I know... I was a bit worried about this but searched around and figured I'd give it a try anyway. I only put half the bottle in. The cooling system needs to be flushed anyway and I will do it when I change the gaskets.

 

[TheJackal]

Well guess who's an idiot

After the past few days the issue just seemed to get worse. I needed this to get done now, so I take it to the dealer for service.

And guess what? Turned out not to be the gasket after all. Would you believe it, all it was was a pinched wire somewhere in the harness going to the coil pack. Although I'm not sure what it got pinched on in the first place...?

In my defense, tho, the gasket DOES leak... but it remains for now to be external only. :exp: