Hi Guys,

I have a 1997 F150 2wd with the 5.4 v8 engine. Truck runs awesome however when it is idling there is a slight stumble in the idle. It idles at around 600 rpm with a slight shudder every 10 seconds. Had a COP replaced about a month ago and the mechanic pulled the plug and said that the plugs looked fine. It has always done this since I bought it 4 months ago. Should I be concerned? anything I can do to fix?

 

I would clean the IAC to be sure it is not hannging up at times.
It contros air for idle.

 

Im in the same boat as we speak. Mine only does it NOTICEABLY when its in gear. Once you get to higher RPMs, it pretty much stops except once every now and again.

I pulled all plugs and coils yesterday, plugs only have 8K miles on them and they look fine. There was a little water in the spark plug holes, cleaned it all out and cleaned off coils. Its still doing it, not near as bad or as often though. I just put some seafoam in the gas tank, maybe its a dirty injector. My next step is exactly what Bluegrass said, clean the IAC because I haven't done it in over a year and that's probably the real problem here.

 

Don't put that snake oil in the tank. That will do absolutely no good. Now you know

 

The only snake oils for the gas that work are Techron and Gumout with Regane.

 

You guys can think what you want. Yesterday I dumped it in with minimal hopes, but today shes running perfect. But Lucas products are the only thing I run in my truck, whether everyone thinks they work or not.

 

Well, - There's no carbon build in your injectors, but ok lol.

What do we know?

ric14221 - Bluegrass has your answer.

 

If you are going to put Seafoam or Lucas in your tank, save your money and go to a chemical supply house and buy a big old can of Stoddard solvent. Does the same thing.

 

Guys,

If I have the fuel induction service done at AAA car care will that fix it? They want 90.00 to do it. I had the fuel injecters cleaned at firestone about 3 months ago. Again just a slight stumble at idle maybe 50 rpms. Great pick up, runs great, about 14.5 miles to the gallon. Starts easily. It's just I live in Buffalo, NY and don't want to be messing around in the winter. Thanks for all the replys

 

Its only 8-10 bucks. No real need to buy 5 gallons of it for around $60 (depending where you go). Especially when you dont use it very often.

 

I second the Lucas Products!

 

It's your engines, you can do anything you want to them.

 

What's wrong with the Lucas Products?

 

All the Lucas oil treatment does is thicken the oil - which is exactly what you do NOT want to do in a Triton, ESPECIALLY a 5.4 3V. The fuel treatment is no better than straight Stoddard solvent.

 

Right , you'll starve your internals using that crap (crankcase). The smaller galleys and oil soak ports can clot or just get missed. Tolerance's and tight specs now with these engines Sometimes just following the manufacturers instruction and suggestion can net you the most healthy miles out of these engine.

Each injector has a screen filter at the top. These should be replaced / then sonic cleaned and flow tested. Hell, 19's are cheap enough to find new and for sale to just replace. Injector clean - http://fordfuelinjection.com/?p=82


I've seen that Seafoam damage the converters (melting the cones together) and hydrolock the engine (from booster suck up)