As some of you may know by following my threads, I've had some woes with my Expedition. I've replaced just about every fluid line that can leak and was still having some severe drivability issues. I had thought that I had a clogged catalytic converter so I replaced it with pipe and still had the issue. I took it in to a shop to get the codes pulled and got the following results:

Misfire on cylinders 1,3,4,5 (P0301 etc)
PCM reset (P1000)
Throttle position sensor inconsistent with MAF (P1121)
Cylinder head over temp (P1285)
Engine over temp (P1299)

Now, the over temp readings I understand due to the thermostat sticking. The misfire I'm assuming is because of the plugs? I have the truck at another shop to get the plugs and wires done. Hopefully the misfire is due to the plugs and not the injectors; when I replaced the intake manifold I had to replace a few of the injectors due to them getting damaged in the process. Finally, looks like I need a TPS as well? Or is there a problem with the MAF, potentially?

 

I dont see where you say what engine could be wires need changed or coils if 5.4 or coil paks if 4.6. Clean the MAf. P1000 isnt really a problem just needs to go through a few drive cycles. the over heating deal could be bad. hope the engine dont have a major problem..

 

What engine ?

 

Sounds like it got wet regardless, packs or independent coils-



Or a fuel filter, fail safe don't make sense w/missing cylinders, although, -still possible.

 

Sorry, my bad. Its a 4.6L. The fuel filter on this truck is pretty new from the looks of it. I had 7/8 of the plugs out when I was tearing into the engine (didn't get #4) and they looked okay but they were Bosch ones of some sort. Could've been bad after all and new wires certainly will help. And I'm sure there's a bunch of coolant everywhere as I blew a line off the other day too (although it had a misfire BEFORE that line came undone).

As for the overheating, I think its just the thermostat being sticky. I would let it run for a while and I was driving it down the road once and the temp gauge shot up to H and the check coolant light came on and before I could get it pulled over the gauge went back down. I figure the thermostat finally opened. I did buy a new one to put in.

 

Yea, as soon as coolant hits the font of the engine and because the motor is tilted , coolant runs down the top of heads and fills the plug chambers.

I'd thro a set of Motorcraft plugs in it/ Coils/ Wires. But that's me, I don't like pulling my hair out dealing with screwed up ignition components. Once they've gotten wet, their unreliable.

 

An update on my progress with this truck...

I had the plugs and wires replaced (Motorcraft plugs and Carquest wires). The truck runs great now! I also replaced the TPS and ended up having to replace pads and rotors on all four corners as well as a flex hose and a brake line (driving home without brakes wasn't fun!). I'm also having an intermittent misfire; I borrowed my uncle's code reader to check the codes and cleared everything. The only code that came back was misfire on cylinder 4, so I'm thinking I need to change the injector as the misfire isn't constant (which would indicate to me a spark problem).

 

So I've been driving my truck around for a couple of weeks now. I've gone through a tank of gas and filled it up again. I consistently have a misfire in cylinder 4. I just replaced the injector, cleared the codes and went for a drive. The misfire came back. Since the plug is new, the wire to the plug is new, and the injector has been replaced, is it possible that the coil pack is bad? I would think that if it is, the other 3 cylinders that it powers would be misfiring as well...? Of course, there is a possibility that the injector I put in is bad as well.

Here's the freeze frame data from my code reader:
P0304 cylinder 4 misfire detected
Fuel Sys 1 CL
Fuel Sys 2 CL-Fault
Calc Load(%) 72.55
ECT(°F) 185
STFT B1(%) -1.56
LTFT B1(%) 9.38
STFT B2(%) 0.78
LTFT B2(%) 9.38
Eng RPM 1979
Veh Speed (mph) 32

Now I don't really know what all this means, hopefully someone can help out?

 

I can't help you, but what kind of Code Reader reads real time data like you have? I've got a slight misfire at idle and maybe at cruising speeds I'd like to verify w/o taking it to the dealer.

 

Yes you can have just one misefire on a coil. However most of the time it is just dead.

 

Switch the coil packs and clear the codes. Does the miss change cylinders? Yes = coil. No could be connector at coil, injector or its connector/wire, plug wire or plug.

.

 

I have a a set of coil packs on another engine. I'll take one off of it and see what happens.

 

So the plugs and wires being replaced is what fixed the p1299 and p1285? because im having the same problem. just started yesterday on the freeway. saw the light come up. I also have p0442 that is an fuel system code. i dont want to start replacing parts until i get some other ideas out there. The last time the plugs and wires were replaced was like 2-3 years ago.

 

P0442 is small leak in the evap system detected. Gas cap, stuck valve in the canister vent, cracks/splits in the vapor hoses.