(ford)

I just replaced, fuel filter, air filter, spark plugs, and wires. Distributor cap, and rotor.
My truck ran fine before I did the fuel filter, spark plugs, and wires. Now it runs like crap. I checked the wires, replaced the new wires with new wires. terminals were bad on a few wires. Now I'm wondering if, maybe my plugs are just junk, I have been under the hood of my truck for hours, within days. Trying to find what it could be. I have the autolite plugs, in my f150. I have a miss and a backfire, wondering if maybe I should replace the plugs with better plugs. Just doesn't make sense how my truck can run fine before the tune up, and run like crap after. I can see the quality difference between the NGK's and autolites. Would you think, getting better quality plugs would be a good idea? I can't figure this out...
thanks y'all

TylerF150

I personally would go with motorcraft plugs. I've heard of people using autolite and getting same results then upon switching to motorcraft all was back to running good

13Harleyfan

Don't know if you got this resolved yet, but so few changes it sounds like maybe you have a spark plug wire out of sequence.

garbill2003

I agree

(ford)

hey all,

Ended up buying new plugs. The truck stopped missing, and was running better for about 15 mins. After that, it began to have no power. I have another thread about it. I think it says "I'm about fed up with this". Anyways, appreciate the help. I did end up fixing the miss problem. But still have loss of power, and the check eng light is on.

13Harleyfan

Put your old plug wires back on and see if that changes anything, unless a plug is cracked, that should not be part of the problem. I've used autolites/a-c/motorcraft, they are all good plugs. Hope this helps.

crazykarl

My bet is on the autolite plugs. A good auto parts person would have never sold you autolite plugs. I have a 2008 f150 with 4.6 and I put autlites in that advance sold me. When I changed them my truck ran like crap. I went to my friend at autozone and he said he never sells autolite for ford products. You will find a few ford vehicles that will accept them but across the board most wont. I went back to motorcraft and all is well.