Hello all,
New to the forum. I've got a 1998 F150 5.4 Triton Supercab that I'm working out a few issues on.

First one is that I'm getting a lean code (both banks) and have the following symptoms: 1. After I start it up from cold and start driving, it will get to about 40 mph and lose power no matter how much you apply the throttle. It will wake back up after about 5 seconds and run like normal, and it only happens from cold the first time you reach that speed. 2. If you floor it, it takes forever to respond. Very low on power until it catches up after a few seconds and runs fine. 3. Takes a few mores seconds to start than it should, and idles a little bit rough when it settles down to 900ish RPM (it starts at high revs, 1700ish until it settles down after about 10 seconds). Seemed to me like a fuel issue, so I put in a new fuel pump and filter. No change. I'm still leaning towards fuel, but since it's lean on both banks it's got to be something upstream on the fuel rail, what else is there?

Second problem is that the brakes have a ton of travel before they engage, but then they work fine. When I bought the truck the booster pushrod had been extended almost a half an inch too far (for real) and was applying the brakes as soon as the engine warmed up, causing it to shake horribly. Adjusted it back and the brakes worked but just had so much travel before they engaged. Put new calipers, master cylinder, and booster on it and made no difference. Pushrod should be to spec (I have the tool) and I've tried adjusting the rod from the booster to the actual pedal too, but it doesn't make much of a difference. Bled the system after the calipers and master cylinder went on; maybe I didn't do it long enough but considering that the pedal felt the same before and after the job, I feel like it is something else. Could it be the rear brake cylinders? Adjusted the pads to reach the drums (they were pretty close already) and that didn't make a difference either. Kinda stumped on this one.

Also the radio doesn't work lol. Headunit lights up but no sound.

Thanks for coming to my TedTalk. Feel like I should be paying for this kind of help but I am still a recovering grad student with a poverty mindset even though I make real money now.

Thanks
-ac16

 

The low brake pedal issue
Sometimes a service bleed procedure for the ABS HCU is needed
Most of the time it's just the rears being out of adjustment
Good job is school
This is what you need to do a service bleed \
Some other expensive bi directional scan tools may do it too, like a Snap-On

 

I have a Foxwell brand scanner, ran $300 that does ABS bleeds. Forescan may have the ability, never checked.

Low power? Sounds like a dying fuel pump...I would see if the current is installed backwards. Seen it before! If no change, gauge on the rail and tape to windshield.

Radio probably died but not always, could see if the speakers are any good. My beater minivan had three of four dead, headunit still fine. Stock speakers are junk anyway, I have a few headunits here you can have one. Just pay freight. Pioneer A-series 5x7s are good inexpensive drivers.