my 96 f150 4x4 with a 5.0 efi has a problem with shuttering or chugging on startup...sometimes, it does'nt always do this. only on startup it chugs and chugs and most times it comes out of it and idles fine sometimes i can give it a little throttle and it comes out of it. sometimes it chugs and chugs and then dies and i try to keep starting it and sometimes it will restart after trying like 10 times. did it yesterday and i ran the battery down trying to start it. came back in 2 hours jumped it and it fired straight away, no chugging at all, and has been starting fine since. it does it mostly on cold starts but yesterday i had ran some errands, on the last one it did it again, and this time it was warmed up, not the first time it has done this even warmed up. temperature doenst affect it happens hot or cold, doesn't matter if it is rainy or not has happened in both kinds of weather. doent seem to matter which tank i use front or rear....driving me nuts can't figure this one out....once it starts and comes out of this chugging thing...it runs fine and may not happen for a week or 2 or may happen on my next startup...any ideas????

 

While chugging, or after chugging, do you get any brown or excessive smoke from the tailpipe?

 

you know i really haven't looked to check that...am always wondering what it is going to do when this happens...will it die or will it take off this time. at this point in time i can't pin it down to one thing... except it only happens on start up...there are no other particulars that i can find. would the smoke indicate anything???

 

Never ignore the basics.....how old are the plugs/wires/cap/rotor and filters?

Have you checked for any codes?

 

have replaced all the basics over the last couple of years way before this started.....has never thrown a check engine light....haven't checked for any codes. will it give a code even though the check engine light has never lit???

 

Yes, many times there can be stored codes without having the Check Engine Light lit.

A couple of years is a long time IMHO. I would pull the plugs to see what they look like. Plugs have a way of revealing the true story of what is going on inside the engine.While you have the plugs out, crank over engine with a plug grounded. Take a look at what color the spark is. Should be a nice bluish tint.

Had a recent post here where the OP stated the engine had a horrible idle problem. Turned out the new Duralast coil from da' Zone he recently installed was bad.