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Q: What causes my 99 f150 with 4.6 sputter

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What causes my truck to sputter & sometimes die. It has been less than 2 years since I replaced the plugs & wires with Motorcraft items. I even temporarily replaced one of the two coils & it still showed a miss in two of those cylinders. I also replaced the fuel filter about a year ago. I was getting EGR codes. So, I had the throttle body cleaned & replaced the EGR valve & DPFE. Now I'm still getting a very bad miss & even stall fairly often. It seems more common when the engine has warmed up & I have stopped. I get a miss in 4 & 7 or a random multiple misfire or both. Now I'm also getting the code for the crankshaft position sensor. I read that it just applies to starting? It's random too. Sometimes the truck does fine. It seems worse when I have to get on it - like going up a hill. Could it be the crankshaft position sensor? I replaced plug 7 & no change. Egr & miss codes began a few months ago. CPS code is new. Thank you for any help!

My car has 167000 miles.
My car has an automatic transmission.

Hi there. Any unusual shaking, stumbling or vibrating forces coming from the engine is cause for concern. It could be something as simple as old spark plugs producing an uneven power delivery, it could be something serious like fuel delivery, air to fuel mixture or other ignition system issues. In most cases, when a sensor or other mechanical problem exists, a check engine light will illuminate. You might want to have a professional mechanic complete an engine is shaking or vibrating inspection to pinpoint the source of your issue.

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