2005 F-150 5.4
 

I have a 2005 5.4 here. What the truck does is miss at idle. I've tried everything, plugs, plug boots, coil & injector. Works decent on the highway. It's been to the Dealer they can't fix it, after a $1000.00 bill. They said a new engine is the best way to go. What they found is that the right bank has 150lbs of running compression with the left being 180lbs. This truck did have a new VCT cam sprocket in stalled on it late last summer. It ran rough back then after wards but they blamed tune up ect. Now through all this trial & error I decided with compression being low on that side that it must be out of time on the cam. I've taken the front off of the motor, now I realize how complicated it is to work at. I've gotten different info on what the timing should be. There seems to be some conflicting info out there. I know about the gold links but I've turned the motor over & over & they have never even came close. A mechanic told me you have to turn it over up to 64 cycles. What I'd like to know is there a way that I can use the key way on the crank or the dot on the bottom & the marks on the cam sprocket to confirm if it is in or out of time? Any help would be greatly appreciated.
Thanks

I feel for you, but this is why I bought the extended warranty when i bought the truck. If I have to tear an '05 motor apart to fix something, I would drive it thru the front window of the dealer.

You said it yourself; you have a compression imbalance. You'll feel it at idle, but not at higher RPM's. The old Chrysler "K" Cars used to do that, but they would have 4 different sized pistons in a 4-cylinder car. Your options are boring it out, changing the rings if they scope the same sizes, or a hundred other variables.

Sorry

Thanks I was hoping it was something else. I told Ford when they told me that it was best to change the motor, I said if I do I'm gonna put a Dodge or Chevy motor in it. I realize this isn't feasible but I thought it might put them in the same kinda mood that I'm in. I'm fairly used to playin with motors but this one is hard to work at I find.

VAS, did you buy the truck new? Are there a lot of miles on it? I ask this because the Ford Customer assistance program 1-800-392-3673 is there to assist you. FMC will step up before the dealer will as they want your future loyalty. If the truck hasn't been abused or used commercially, I doubt that Ford will allow to be left out in the cold on this one.

Tim

No the truck was bought used & not from the ford dealer. It's past the warranty by quite a bit. Unfortunatly I'm SOL on that front. I know that it can be fixed, the motor was noisy before the VCT cam sprocket was changed but it ran excellent this all came about after this was changed. I'm still thinking this is where the problem is.

What does the dealer base his reason for replacing the motor vs repairing? It appears obvious that if the problem didn't exist until the VCT cam socket was replaced that it is an installation problem. A factory trained techinican should be able to fix it without the need for replacing the motor. Even if the head had to be replaced it would be cheaper than an engine replacement.

Tim, I wish this were true with the spark plug issue on the 5.4...I'm pretty sure they know about it...?

They say it has nothing to do with the VCT that it's in time. They say the motor is obviosly wore out since low compression on right side. I haven't seen an engine wearout equally on one side. Usually the compression will be uneven. since it's on that side & equal I think it's timing. I just can't find out how to time it. Ford says one way & a local mechanic & his book say another way.

There are three copper links on the timing chain. Two on one end and one on the other. When the single link lines up with the dot on the crank sprocket the mark on the cam sprocket should be between the two copper links at the other end. The book cautions that mishandling can damage the phaser.

How many miles are on the truck?

I'm not doubting you, or the dealer at this point, but EACH cylinder on the left bank is 180, and the right 150? That doesn't sound right. There should be variance in each cylinder of 1-2lbs at LEAST. Did they do a wet/leakdown test, or did they simply run a dry compression test? That alone wold tell you a lot. I'm not leaning towards it being a timing issue because you say it runs decent on the highway. If you had a timing issue, it would be bad throughout the power band. I sincerely hope it's not an engine, but if it is, then a rebuild should be less than a new one. You'd be looking at boring it, bigger pistons, new rings, bearings, etc. Cam would probably be good. Let me know about the compression results. Please.

I'm sure that it did vary 1-2 lbs but they said that they were all about 150 lbs. This was a running compression test, they said that when they did a wet test it came up to a bit over 200 lbs. You sound very knowlegable hopefully you can steer me in the right direction. The truck has just under 85K on it.