1999 f150 engine light on.

i just did a tune up in my 1999 f150, with 5.4l. i put new plugs in, changed oil and filter, changed air filter, and now the service engine soon light comes on. after i changed everything it was fine i took it up and down the road a couple of times and on the last time it started to skip a little bit and the light came on. Any ideas on what it could be.
thanks Tim

Taking it to autozone to have the codes read for free would help narrow it dow. My guess would be a bad vacuum line. Might have popped something off or had one of the hard lines crack. good hunting.

you mean they will hook there computer to it for free and tell me what the problem might be. usealy id take a vehicle to the dealership and pay for them to hook there computer up.

you mean they will hook there computer to it for free and tell me what the problem might be. usealy id take a vehicle to the dealership and pay for them to hook there computer up.


Yes, they will hook up a hand held scanner and tell you what codes are present. All for nothing also. It is somewhat limited to mostly generic obdII codes but is most times all you need.

They might even offer advice on repair. Get the codes and post back tho. I have seen some autozone guys who were very good and some who were very new.

You can also look at all your vacuum hoses and connections for leaks. If the hoses are brittle or gummy replace them.

Yes if the light is on they will 4 free check the code. If yours is like mine the coils are on each plug your hands can move a lot of things without u knowing in tight spots. Make sure all coil paks are on good and yes look at all hoses elec plugs etc are all on good.

i was talking to a guy that i work with and he told me that it could be that one of the coils could be bad. what is the odds that a coil could go bad and need to be replaced. thanks guys

i was talking to a guy that i work with and he told me that it could be that one of the coils could be bad. what is the odds that a coil could go bad and need to be replaced. thanks guys

It is possible. Having the codes read will tell you which cylinder has a missfire. Most autozones can even test coils free of charge. They must be removed and brought into the store.

Too many possibilitiese to just guess and throw parts on without knowing for sure.