i got a 97 with close to 200k it idles rough and almost like a "skip" on acceleration. at idle it sounds like it has a cam and shakes the whole truck

 

Which engine? Check the OBD2 for codes.

 

I think this is a test, we're suppose to automatically know or maybe it's not suppose to matter ? Either way, if I wanted some good free advice/help, I would sure as hell detail my info for the best possible outcome.

Like what I have done so far to try and figure this out.

 

Well, he posted in the V-8 forum so I guess we have a 50% chance of guessing correctly. Kinda makes a big difference, in 97 the ignition systems were totally different.

 

I'll guess, - Big Cam @ idle, miss under acceleration. Sounds like more of a six cylinder problem (4.2L), but this is the V8 forum, I'll give him the benefit of the doubt and say he has a 4.6L.

Don't quote me , I may have to edit later.

 

actually thought about all of that when i woke up this morning.
its the 5.4
automatic
and so far i have changed plugs and all 8 coil packs
tried using 93 octane tried fuel injector cleaner

 

Geezz, I was way off guessing lol. Not doing that anymore.

5fours don't use coil packs, just coils. The 4two and older 4six's use coil packs.

What coils did you use?

What plugs did you go with?

And you haven't answered glc, - did you scan it, or have it scanned for DTC codes?

 

i got the cop's from global and used motorcraft plugs from a local auto parts store. i havent had it scanned because the check engine light hasnt came on at all. so i just changed all of that thinking it was just regular maintenance. since i changed all of that it seems to be sucking down fuel maybe just coinscidence not sure?

 

So you changed the coils and plugs and the only change noticed, -it's sucking more fuel.

It's running exactly the same as it was before you updated the hardware? No change? New plugs ,New coils, No change right?

 

correct. so im thinking it was something more then that if that at all maybe the iac valve? i took the air intake tube off and the tb has a sticker that says not to use cleaner on it so?

 

Nah, not the IAC, don't take anything apart yet.

Next time your at Auto Zone, have it scanned anyway. The CEL will blink then shut off when misfiring, you may have a DTC on the KAM and not know it.

You need to check Fuel Delivery first, check the pressure per Haynes or Chiltons manuals.

Keep an eye on your cats in your travels as well, look for one side heating up more than the other. Could have melted the cone together at some point, just keep an eye on them for now with those miles. Check the fuel pressure ASAP and see if there's a code when scanned. The CEL doesn't have to be on to produce a fault code, have them scan it regardless, - IT'S FREE.

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Also, read from post #7 here - https://www.f150online.com/forums/v8...y-circuit.html

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CEL- CheckEngineLight
DTC- DiagnosticTroubleCode
KAM- KeepAliveMemory
ASAP- FrickenPronto