I have a new 2001 F-150 w/ 5.4L V-8. When at idle, the engine seems to miss every few seconds. Is this normal? or is it a bad injector or sparkplug? The truck has less than 2000 miles on it.

What do you think? Does it merit a multi-hour trip to the dealer?

 

Mine has never done that. 6000 miles now.

2000 XLT Flare Supercab Sport 5.4-Auto-355LS-Tow pkg-Bedrug-Xtang Tonneau

 

[font size="1" color="#FF0000"]LAST EDITED ON 21-Oct-00 AT 05:23 PM (EST)[/font][p]I have the same problem with my 1999 F-150 5.4. I have taken my truck back to the dealer twise for this problem. I even put a glass of water in the console to show them it idled so rough that the water spills out of the glass. They told me twise that the diagnostics does not show a problem,thus they have no repair procedure.I went to fords Recalls/TSBs web site and found that this problem was reported to ford back in April-99. PLEASE PASS THE WORD to get a recall on this problem. Ist call NHTSA TSB database at 888-327-4236 and report this problem. 2nd take your truck back to your dealer once a month for this problem,Ford will have to address this problem. I have 14,000mi on my truck and have had it in to servise 3 times. I have had this on numerous message boards and have had over a 1,000 hits on this very problem.You are not imagining this the dealer calls it engine vibration. HELP GET THIS RECALLED

 

My guess would be a cracked "coil pack" on one of the spark plugs. You will not get a code unless the same cylinder misfires continuosly for 2 minutes. I had a cracked coil pack on the right rear cylinder and experienced intermittent missing. Turns out the heater hose above the coil was dripping coolant on the coil and probably induced the failure. Check your heater hoses and the coil packs. New coil packs are about $47 from the dealer. I could never understand why the truck would be running great when I parked it in the driveway and would run rough when I would go drive it later. Turns out the radiator coolant pressure would cause the heater hose leak and wet the coil pack.

 

I have experienced the same problem with my truck except I have a 2000 F-150 with the 5.4. My truck started to do it at 7700 miles. They have tried everything to fix the problem. They installed a new fuel rail, injectors, sensors, and many other parts. It has had no effect. The idea on the coil is something they have not tried. My truck has a rough idle and would spudder when a first accelerated after I just start it. Try the coil because everything else has been tried on mine.

They plan on getting me a new truck but it will cost me some money. The claim settlement board, which is through ford, will decide. They've treated me good at my local dealer but I'm assuming this will change now that they're looking at finding me a new truck.

 

Fords ignition system has 2 spark ignitions one for power and one for the exhaust to burn more polutants thats why the 2 different spark plugs from the factory and when you replace them you put the double sparking plugs on both banks. They burn/spark twice to help pollution emmissions thats the rough idle it normal

 

Which model are you referring to?

I remember only one engine that Ford used dual plugs on (in th US), the 2.3L I4.

I have the 4.2L V6 in my truck. There is only one plug per cylinder. On a V6 DIS (distributerless ingition system), such as mine, there are three coils in the coil-pack, with two spark plug leads each. When it's time for one cylinder to fire, the other cylinder attached to that coil fires as well. I think this happens when that cylinder is 360 degrees from when it needs to fire (near the end of the exhaust stroke).

The fire on the exhaust stroke is not to try to burn extra pollutants, I don't believe. The amount of fuel still present is minimal, and it's not compressed. So the spark would not ignite much, if anything. I think the only advantage of firing on the exhaust stroke would be that it might help clean the plug. Really, I think it's just an inconsequential side effect of the design. There may be a disadvantage of shorter plug life even.

If you have a dual plug engine, both plugs would fire simultaneously (on compression and exhaust stroke). The advantage would be faster and possibly more complete burn.

The company I recently worked for, makes tooling for Ford 5.4L and 6.8L heads. They only have one plug per cylinder, also. We did make tooling for some prototype Cobra heads, in both a single plug and a dual plug version. But, that's a different story.