Q: What causes my 99 f150 with 4.6 sputter

asked by

Scott J

on January 10, 2017

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.

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Q: What causes my 99 f150 with 4.6 sputter

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