I replaced the O2 Sensors with no luck. L is still down on power and mileage sucks. When I nail it, it pulls but @ about 3500 its got a stumble then it picks up again. Also feels like I'm making noise and not running like I used to. Fuel filter is changed with every oil change.Next up is coil packs. Do I replace them in pairs? I read where the cyls kinda work with each other or something. I also understand that #s 3&8 are the likely culprits is this true? How exactly are the cyls numbered? Do I replace the boots also? Thanks in advance for any help, I read alot of info on this site. Having a Stock L, I just never ask or post alot of unnecessary ??s.
Dave

 

Threemore ?s Does it matter what brand coil pack I use? Pep Boys had Borg Warner with a 12 month warranty. Where to buy NGK TR6s and do they need to be iridum or standard. I'm guessing that 4177 is the part #
Thanks
Dave

 

Ne1??

 

Go to an Autozone and have them check to see if your L is throwing a code. If so this will tell which coil is bad so you dont replace the wrong one.

 

Tried that and the dude told me since I didn't have a SES Light on their code reader wouldn't tell me anything. Thanks any way
Dave

 

Hey man, don't feel alone on this one..I'm going through the same thing of scratching my head wondering what's causing my L to be down on power.. I think the high milage (120K miles) has something to do with mines.. I've changed everything all except my coil packs.. Just haven't been able to afford them w/ every other financial obligation I got going on.. The cheapest I've found them for is from one of the vendors on this forum.. I'll look them up and give you the name.. They want 500 bucks for the set (Ford factory).. how many miles are on your L? If i'm not mistaken I don't believe you have to throw a code in order for them not to fire correctly.. Over time I think they lose their spark/voltage hence causes stumbling/bad throttle response.. Just have someone test each one to see if they are firing all the same.. W/ my milage i'm just going to buy the whole set instead of replacing a few... If it's not my coils, i'm checking my catylic converters and stall/torque converter...

 

look under LFP's website.. They seem to have the cheapest price on coil packs so far

 

Thanks alot. I've got 53k on mine. I bought 4 Borg Warner Coil Packs from Pep Boys for 42.99 ea. I ordered a set of NGKs part # 4477, TR5 Iridiums. I'm gonna do the resistance checks and try to find a bad coil. IF I don't find one I'm gonna change at least four. My L is stock except for Maggy cat back abd a K&N.
Dave

 

Let me know how those coil packs work out for you..I may go to pep boys and get some too

 

One good thing about them is they have a 12 month warranty. They price matched ORielly. If you get them from ORielly they have a lifetime warranty. At least that is what the guy here in Corpus Christi told me. Would've got them there but it would take 5-7 days.

 

This test tool has proven very good at checking coils with the motor running. Just power brake the motor a little to make it miss and touch the tool to the top of coils. It will flash a red light if coil is firing poorly and a green light if OK.

http://www.shop.com/op/aprod-p23918178?sourceid=3

 

Get TR6's(4177). -Mat-

 

no code will be thrown if a coil pack is going bad. heat equals resistance for electricity. when my truck is at operating temp and its over 70 out i had a bad miss anytime i got into boost. the truck would spit and spudder and act like it wanted to die only in boost. since its cooler out it hasnt done it, or been so noticeable. i still havent replaced any coils packs but i need to so nothing gets messed up.

you should be able to unplug one coil pack at a time to find the bad one or ones. unplug one and if the truck runs worse then before you know that one was good. keep unplugging one at a time until the truck runs the same as it did with it plugged in and you found your bad one.

 

The 4177s are not Iridiums are they? Hopefully I got plugs that will work. (4477s) They cost enough 106 bucks and change @ NAPA and that included the active duty discount.

 

Hey 02 bolt.. Have you installed your new coil packs yet? Let me know how they are working.. I was kinda skeptical about going with the coil packs outside of the Ford manufactured.. I kind of remember someone told me that other brands didn't have the same electrical/voltage capacity as fords.. If they are working for you and your trucks performance is good I'll go get a set.. Just wanted to know, maybe that person could have been wrong??