I have a 2004 f-150 with the 4.6 motor. It has been in the shop numerious times for engine problems. Three times for fuel related problems where it runs out when it is not empty. One time both heads were replaced. A month later started running like crap again and ford said that one of the spark pluds gap was closed completely. Now how could that happen. Now another month later it has failed again. This time they say one of the cylindars has lost compression again and they are going to replace the heads again. I am not a mechanic but I do know that this is not something that should be happening to a truck with 30,000 miles on it. Anyone else having problems like this.

 

Stand up and say "drop in a complete NEW motor". And make sure it's a complete motor, COPs, injectors, intake, etc. For what they are going to charge Ford in labor to replace the heads, they should just put in a new motor.

Or, bring it to another dealer and tell them what the other dealer's already put you through.

 

A plug in which the gap has been bridged by deposits almost certainly has a problem with blowby. No head replacement will fix that, since the problem is with they piston, rings, or a scored cylinder. Why they'd want to replace the heads again is lost on me.

I agree with the previous poster that your truck needs a new engine.

You already may be due a new truck under your state's lemon law. I'd seriously consider consulting a lawyer.

 

By saying the plug gap was closed, he might mean the electrode was aganist the tip. The only two ways I can think of that happening is the rod bearings are loose and the piston came up and smacked the plug, or foriegn material got into the cylinder and was pushed into the plug by the piston.

If anti-freeze was allowed to get into the pan when the heads came off the first time, and not completely flushed out, then the rod bearings could be shot.

Why did they replace the heads the first time? I am hearing a knock toward the rear of my drivers side head on my 03 4.6 Expy. I hope it is not head time, no warranty.


Here is a portion of an article at remanufactured.com

Old Wives Tale number 53.

The engine starts to use oil so a valve job is performed to correct the problem.

Immediately afterward the engine starts knocking or ticking.

The misdiagnosis is that the valve job gave the engine too much power making the weak bottom end fail.

What really happens is that mechanics all around the world burp the heads and timing covers off without draining the coolant from the engine first. The coolant spills into the bottom end of the engine. Even one oil change may not get all of the spilled glycol antifreeze out.

When you mix the smallest amount of antifreeze and water with motor oil you end up with a low grade acid that attacks the bearings. When you autopsy the engine you will find that the bearings are darkened and with time the bearing surface becomes rough.

That's why it developed a bearing knock immediately after the heads were done.

Carelessness or ignorance.

The right way is to open the drains or knock a freeze plug out.

Vee engines have two separate water jackets on each side so don't for get that you have two drains, one each for the right and left.

 

The first time the heads were replaced was cylinder 0 had no compression. My thinking on the plug gap was they installed the plug that way but it would not have worked from the start. There is no knocking at all in the lower end. This time cylinder 3 has no compresssion. They are telling me that it is too early for the lemon law only 2 times for same thing

 

There is no cylinder "0".

 

That's why it has no compression

 

ok cylindar 1

 

Sounds like a valvetrain problem. I would try to get a complete longblock from them this time!!

 

I agree with everyone else, time for a new engine. Sounds like the current engine may have been assembled on a Friday afternoon at 4:30 p.m.

 

Or Monday @ 7am after a long holiday weekend drunkfest

 

Just got the reply back from Ford and they are not going to replace the motor. They said that they would only replace the heads again. Also said that it does not qualify as a lemon law yet. I guess my next truck may not be a ford.

 

Cunsult with an attorney, and see if they say the same.

 

I completely agree. There's no reason for them to jerk you around like this.

 

well its still in the shop but the good thing is the dealer told ford that replacing the heads again was not going to correct the problem because there is corrosion in the motor. A ford rep came out and inspected the motor and they have decided to replace the motor. It is supposed to be done any day now.