My 5.4 Ltr has 67000 miles at 63000 miles it started to surge & miss at low r.p.m. , the diagnosis was coil failure so we replaced 2 of them. Now 4000 miles later the surge has reoccured. I will be replacing the remaining coils (6) & the spark plugs. Is this common of the 5.4 Ltr motor to have the coils go bad. What causes the coils to fail & should this be expected every 60k miles or so. Is it something else that could have caused the coils to go bad ?

 

well i'm not a ford tech but still. do you do any kind of offroading/muddin that could cause dirt and mud and water to get all over your engine? alot of times water can cause the coils to fail.

 

Coils just don't fail on the 3V. At least not as often as on previous engines; in four years since the engine was first released, I can count the number of failed ignition coils I've had to replace on those on one hand.

Barring water intrusion like Matt mentioned, you need to start checking things that'd affect all cylinders - start with fuel pressure, volume and quality.

 

I have done NO offroading at all since day 1 of ownership, my truck is modified just for show & is my daily driver. I do however go through the local car wash & now that I think about it they do powerwash the front grill & bumper area, this may be part of the culprit do you think thats possibly the cause ??

 

Is there a fuel pressure / volume test of some kind ? I do have a programmer (Edge) but the only thing set is the wheel size I've done no other changes to the edge & thats been on now for about a year or so.

 

No its fairly common to replace coils on fords it seems based on our shop. When they start to fail around 60-100k miles its best to replace them all at once or you will replace them all over a period of time. When you do that you might as well do spark plugs since they are usually orginal too. Make sure you use anti-seize compound when you do spark plugs too. Alot of Ford cars/trucks did not have it from the factory, and some people are having issues of them breaking during removal. Take your time and work them out slow and easy.

 

i will agree the 3v coils do fail alot less then the 2v ones.

if it is indeed coil troubles not related to water. change the plugs. carbon buildup and excessive plug gaps can make the coils need to put out about 20,000 more volts to jump the gap and they dont like that. Ford says 100,000 miles i say BS. i have pulled plugs at half that and the gap is huge...

if you would like to check your injectors with your edge do this.
-display the FRP pid.
-KOEO(key on engine OFF)
-watch the fuel pressure. it should stay constant at around 40psi. if it drops there is a problem.

 

Before you change the plugs on a 3V, you need to spend some time reading threads and get a copy of the latest TSB. If you just go in there with a plug wrench and try to take them out without doing your homework first, I almost guarantee that you will break them off in the heads.

 

Well your right the 1st plug removal did in fact brake. Now theres a LOT more of an issue that I have. With the help of a friend who has a MAC tool truck he let me borrow the special broken plug removal tool. What I PIA that was. So yes the next 2 plugs broke off as well. I shall make another attemp next week for the other 5.

After replacing ALL the coils & 3 plugs, the motor still produces a shutter / miss at low r.p.m. only. Any help here ????

 

finish the rest of the plugs and then see what you got from there.

 

Did you follow the TSB to remove the plugs? You do NOT just go after them with a plug wrench!

 

I had that happen sputter & miss at low RPM and sometimes it would not start like it should sometimes I had to turn the key 2-3 times I took it to the dealer and they found one of the injectors No 5 were bad

Here are the
FP Number 5C3Z - 9F593 - DC
Description Injector Assembly

Good Luck

I did get a Check engine light once but it went away by itself again.

 

the 05's had injector problems. his is an 04, they werent known for bad injectors but its a possibility. but like i said the plugs need to be finished. he has 3 cylinders running strong and the rest are a little weaker which can cause the engine to sputter.

 

Love your Go-Rhino Chrome push bar, I installed the same unit on my 2007 XLT!.........

 

I seen a link about plug changing in the technical article section but the link was bad, I also did a search here & nothing came up under a search for spark plug change, Can you attatch the link in my post for reference ?? Please !