Abcdefghij

 

A loose spark plug will leak hot gasses up into the spark plug well and overheat the COP. This would explain both the misfire and the burning smell. Was the spark plug and COP discussed and ruled out?

 

Abcdefghij

 

I suggest that you take it to another, independent, shop for an estimate/diagnosis. I think you might be getting taken to the cleaners.
If you do let them do the work you should ask for the old parts that they are replacing. Even if you throw them away later.

 

I agree with that! Any mechanic should be able to troubleshoot that for far less. I wouldn't pay $700 to hear that crap! I've never swapped the intake on this motor. But I've done it on a lot of others. Not to hard, takes some time but should be no issue for a weekend job. Youtube some videos on it.

 

If you are mechanically inclined it isn't that hard of a job. I didn't find it any different than doing intakes on the older 302 Ford engines. Just a few tight spots and unseen bolts to deal with.

Most shops are here are charging around $100.00 per hour for labor. But I don't think that is a 6 to 10 hour job. I say that having done the job myself, not by what the books say it should take.

One tactic mechanics use when they really don't want to do a job is to give you a crazy high price. Mabey that is what is going on.

I'm not sure I can swallow the diagnosis on this one with what you have said. I would second the suggestion to have someone else look at it. This could be nothing more than a bad coil on cylinder 4. That cylinder is infamous for having its coils fail early due to water dripping on it from the heater hoses directly above it.

Here is a pic of the bottom of a 5.4 intake manifold:



Before seeing that picture I would have sworn coolant did not go through the rear of the intake. The blue gaskets at the 4 corners of the intake would suggest otherwise I guess.

I would think a bad gasket or manifold could be identified by a simple cooling system pressure test.

Have you lost any coolant from the system?

 

Hey there, I am having the same sort of problems and was posting on this thread:

https://www.ford-trucks.com/forums/1...and-p0300.html

Pinellas, when you did yours did it just prove to be the gaskets or did you replace the manifold too? The job wouldn't be hard *except* our expedition sites up so high and the engine is so far back. I usually use a full size ladder and it slips out form under me when stretching to get to the rear of the engine...would hate to do a 4 hour job this way.

Any help and tips are appreciated!

 

I had to take my intake out because I was removing the cylinder heads. So I wasn't having any of the symptoms listed in this thread. The original manifold was fine and was put back on the motor.

If you take the cooling fan and fan shroud out you can then used the radiator core support as a chair. Your back and ribs will thank you. Well your ribs will anyway.

 

There is also a lot to be said for removing the hood.