Need help, desperate with my '03, V8 4.6 liter

[Don40]

We've been having problems with our Explorer limited. It was running fine then driving down the highway, the check engine light started flashing. When I got off of the exit & came to a stop, I noticed the idle was rough & the car acted almost like if it's out of gas. I could put it in neutral, rev the engine & the shake seemed to go away. I hooked it up to the computer & got a P0300 code. I changed the spark plugs, pcv, air filter, fuel filter ect. Got a P0304 code, ran seafoam through it, checked the coil pack & tested it again. This time got a P0308 code. I racked my brain & others & didn't know what else to do. Today I took it to Ford to diagnose it. It cost me $217.00 to get a diagnosis. They say that there's no compression in cyllinder #8 & that both valves are stuck open. It's missing pretty much all of the time & there also seems to be raw fuel coming out of the exhaust. The mileage has dropped from 17-18, to 10-11mpg. Ford wants to tear the head off & check to see if there's damage inside. They put a scope down inside the motor & they see that both valves are open which they aren't suppose to be. I brought it home to work on it myself. What should I do next? Any help, I don't want to have to dump 1000's into it. What I'm going to do next is pull the valve cover & see if it's a broken valve spring. HELP!! What are the chances that the valve hit a piston, the guys at Ford said that the scope wouldn't go down into the motor far enough to see. Thanks!!!

 

[zerodevil]

id say you have a high probability of internal damage from such an occurance. Odds are the valves have been struck and there is probable damage to both the valve and the piston, this engine will need SERIOUS tooling before its safe to drive again. i hate to be the bearer of bad news but this will not be as simple as replacing some valve springs and calling it good. If your mechanicaly inclined, you could pull the engine, and do a rebuild for around 600 bucks assuming you have a cherry picker + engine stand + tools already. If not, you could buy an engine from a wreaker yard for 1000 -1300 bucks (i got an 05 engine with about 10,000 miles for 1150 bucks) and take a weekend to put it in yourself. OTHERWISE, your looking at 1000's at a mechanic shop to have them do one of the above options. The cylender head will need to come off to see if there has been any damage to the pistons or the head itself. the valves are likely shot either way and will need to be replaced... good luck and keep us in the loop bud.


p.s. for future referance, when your CEL comes on and is flashing, your best bet to prevent further damage + complications is to pull off the road and kill the engine. a 60 doller tow could save you hundreds at a repair garage.. It is likely your continual driving of it and revving it may have caused further harm to the engine.

 

[Don40]

Yes I am mechanically inclined. My friend has a shop so we are going to pull the motor & take the head off & look at it, you can't get the head off without pulling the motor. Did this happen to you or do you have an 05 motor for sale? What motors can I put in this car that would work with my computer. Any other ideas?

 

[zerodevil]

any of the 4.6L explorer/mountie engines will work from 2002-2005. Just make sure you swap over things like intake manifolds + throttle bodys. Pretty much your buying a long block and moving all of hte electronics over to the new engine. I bought and 05 engine becuase i was having troubles with mine shooting spark plugs.

 

[bookbinder]

I have an 02 with the 4.6 that started the rough idle at stop signs and no power. On the way home from Lowe's the SES came on and started flashing then went off. Had a battery problem during this last cold snap and replaced it. SES quit coming on. Got the SES on the way home from work last night. Went to Sears this morning and purchased an Actron 9175. It showed P0308. I figured the best place to start was the coil and plug. Pulled the coil and boot cleaned them up. Wife had to get hers out so had to button it up real quick before I had the chance to pull the plug. Long story short I decided I would see if that had any effect. Drove around for 30 minutes and had the scanner connected. Erased all previous codes. Drove for another 30 minutes and checked codes every five as I had no rough running/idle problems. Scanner came back no codes PASS. Everything tested fine. One misfiring cylinder will present running rich to computer and it will try to lean back the mixture. Don't know if any of this helps but thought it might be worth a shot. BTW do you own a compression gauge? be sure and check compression for yourself before tearing in to it. Rick

 

[jakedrew]

update?

 

[Don40]

I pulled the whole engine out. The valve spring on #8 was broke. The outside of the spring looked good. Once we pulled the motor the back side of the spring is where you could see that it was broken. We had the torque converter rebuilt, replaced the broken spring, tune up. Put the motor back in & it runs great. Except, the front driver & passenger heat blows cold air only, no hot. So, I unhooked the ac & the heater is working great. I need to put some freon into the ac & hook it back up. The car has been running great except that there's been a rattling noise at start up that is now progressively getting worse. My wife says that it didn't make this noise before. So, yesterday, I started investigating it. From what I can see the timing chain is loose. I can see & feel that it's loose & that's what is making the rattling noise. We didn't mess with that part of the engine when we pulled it for the valve spring. Any help?

 

[sportrac03]

the engines in 04 and 05 are different then 02 and 03. Make sure that you match the engine tags on the motors.

 

[jrford]

"rattling noise at start" believe it or not what oil filter are you using? I had bought a fram and on startup i'd get a second or two of valve tappets, Motorcraft fixed it or I tossed a bad filter with a bad drain back valve.