I bought a 2001 F150 last week. After one day of driving, engine light came on. Took it to the dealer and they replaced the #8 coil and plug. The truck ran fine for about 2 days and then started missing while accelerating. I'd heard there are a lot of problems with the coil packs so I bought a set of 8 coil packs off of ebay and replaced them all, with new spark plugs. It ran good for a day or so but now the missing is worse then ever. I'm really getting frustrated b/c there is now engine light coming on and I don't know what the problem is. Could this be caused by anything else, i.e. the EGR valve, fuel injector, etc? I need help!!! Thanks.

 

Have you changed the fuel filter? Maybe bad gas? What replacement plugs did you use?

 

I used motorcraft platinum plugs. After reading many threads, I found that most people recommend these over bosch or autolite.

Fuel filter, eh? I've seen that a few places. What I don't understand is that it misses, bucks, and jerks only at light acceleration but when you tromp on the gas, it goes with no problem. If it was a fuel filter/fuel injector that was restricting fuel, I would think it would be worse when it's floored. Any thoughts anyone??

 

I should say misses, bucks and jerks worse at light acceleration at speeds above 40 mph.

 

Maybe an oxygen sensor went bad? I'd bring the truck to Autozone or your local parts store, they can check the code and see what's wrong...autozone does it for free!

 

The service engine light does not come on so there wouldn't be any code, would there?

 

Huh?

If the check engine light came on recently, there should still be a code stored....I'd get it checked at the parts store, even if the light isn't on right now.

 

Oops....I meant there is no engine light, not now. Sorry for the confusion.

 

Jeff did you buy the truck at a dealer? Did they give you any warranty on it?
Your dealer can use their WDS scan tool to find the misfire. It can be used while driving to watch the cylinder power balance. It usually shows quite easily which cylinder is misfiring. Once they know which cylinder it is then the COP, plug, injector etc can all be checked.
Were the COPs you bought off Ebay new?

 

Since the repair didn't fix the truck, take it back and they should rescan it to see what is going on.

 

I did buy it from a car lot and they do have a warrenty....30 days, 1000 mile 50/50 warranty. Not very good. My thought was that I could buy all the coils on Ebay and replace them and the spark plugs myself for less then the half I would have pay if I took it back and they had to replace them.

And yes, the coils from Ebay were new, but aftermarket of course I bought 8 coils for $150.

I think I'm going to have to bite the bullet and take it back to the dealer for repair....which is 60 miles away (which is another reason I've been trying to fix it myself!!!).

Thanks everyone so much for the feedback. This site is very valuable.

 

Jeff I have had the same problem with my 2001 f 150. purchased it new and replaced two coil with in 50,000 miles. I think the 2001 built trucks were built using defected coil and ford should stand behind them regardless of miles. buck

 

I had the same thing on my 2000 f150
turned to be a insulating tube from the coil pack to the spark plug.
The dealer replaced the plug ,tube and COP
Next week another one went out.
$180 each time.

 

I've replaced all the plugs and coil packs. Took it into the dealer to get fixed. They've had it for about a day and a half now and still no word. Will keep everyone posted.

 

Okay, so here's the 411. The day after I bought the truck, I was driving around and noticed a miss and had a check engine light on. I took it back to the dealer and they replaced the #8 coil. They replaced the coil and plug. After this, I read many threads on how coils fail so I purchased a set of 8 on ebay and relaced the remaining 7. Continued to have a miss.

Finally got it back from Ford. Turns out the #8 coil was bad. Apparently the coil was faulty. They had to run an engine power balance and analysis to find this though so I didn't feel too bad. So, problem solved.