Hey all! Just bought my 1st Ford truck, super stoked!

2002 Ford F-150 Lariat SuperCrew w/ 194k miles

I bought it with a known salvage title. The truck was rear-ended and needs a new bed, tailgate, bumper etc. Also, a quick look under the front end before purchase revealed that it needed new upper and lower ball joints. There are a few things I didn't notice before I bought the truck that are coming to light a few days into ownership that I would like some advice on.

*** A little background info on me, I am a very mechanically inclined individual. I've done many engine swaps, clutch jobs, brake jobs, etc. I've spent countless hours working on manual transmission cars, but haven't touched a truck or auto trans, so this is all rather new to me.

Issue 1: The air only blows out of the defrost vents. I know that damn near every vehicle defaults to defrost vent only when the system has an issue. I've read up and found that these trucks operate off a vacuum system. Are there any known locations that go bad on this system? Keep in mind I plan on replacing ALL of the vacuum lines in the next 5k miles considering the age of the vehicle, but with winter around the counter I would like to fix this issue ASAP.

Issue 2: The overdrive doesn't kick in sometimes at highway speeds, but kicks in prematurely during around town driving. This results in hard downshifts out of OD. The truck drives and shifts like a dream around town with OD off, but has issues with OD on.

Issue 3: (maybe not an issue?) One very cold morning on my drive to work the "Service Engine Soon" light (CEL?) came on. Pulled the code and it was P0171 which is apparently very common. However, cleared the code about 2 days ago and it hasn't returned. On a separate occasion, with CEL light off, I stopped at a light and had erroneous idling that cleared by the next light and hasn't returned since.

Issue 4: The ABS light is on. Not a huge concern for me considering I've NEVER had ABS before on any of my vehicles. Just wondering if this may be an easy repair?

On the 200k miles mark I plan on performing the following services:
- All spark plugs replaced with Motorcraft Platinum plugs (from my research through these forums, thanks!)
- All plug boots
- Oil change, duh
- Transmission fluid flush and fill
- Coolant system flush and fill w/ new thermostat (Maybe waterpump? Thoughts?)
- New accessory belt with new idlers and tensioners
- Rear diff fluid change
- Transfer case fluid change
- Replace lower control arms w/ upper and lower ball joints
- Replace front and rear shocks (Fox Racing)

I also plan on installing 2" torsion keys up front, with a 3" body lift all around.
I want to run these (5-135 to 5-127 bolt-on adapters): 4 WHEEL ADAPTERS / SPACERS | 5X135 TO 5X5 | 1.5" INCH THICK +20 FREE 1 ? Integrity Automotive / Wheel Adapters USA

My goal is to run 315/70/17 Nitto Terra Grapplers on these: Trophy - D551 - Fuel Off-Road Wheels
17x8.5 +6 et (to compensate for the 1.5" spacer/adapters)

Any and all thoughts are welcome, and thank you for your input ahead of time! I look forward to my time with this AWESOME truck!

-Max

 

air flow to defrost is vacuum leak..... p0171 is vacuum leak causing excess air at O2 sensor...Your looking for cracked / burn hose in the engine compartment... change all as you said.

ABS sensors are one on each front wheel and one on the rear pumpkin. ( 3 total).. Check when the light comes on... when you turn on the key and start the truck the light comes on, does a continuity type test of the wires to the sensor and back. If all is well, the light goes back out. If the light is on constant, then one sensor is bad or not connected... After the motor is running, the ABS light should go out. Put in gear and start moving. A second "test" is that the system must see tire rotation about equal on all 3 sensors when you get to 5-10 MPH... If not, the light comes back on... Normally that means the sensor had continuity since the light originally went out, but now it can not send a rotating signal.. possibly bad sensor, or not setting properly inside the hole.

 

PO171 code

https://www.ford-trucks.com/forums/1...-4l-vin-l.html

 

Steve, thanks for the reply!

The ABS light is solid from the moment I start the engine, whether I'm moving or not. Any way you know of to test the sensors to determine the faulty one (or more)? If there's one thing I really hate doing, it's throwing parts at a problem with the hopes that it'll be fixed. I've always done fool-proof diagnostics to narrow the problem down to a specific part before I replace with new. For instance, i had a wheel speed sensor go out and in order to determine which one went out I had to hook the old Fluke up to the sensors to test which one wasn't giving off a signal when the tire was rotated. Is that process similar for these ABS sensors?

 

Yes, the wheel speed sensor is the ABS sensor.. There is one inside each front wheel hub. Take off the tire/ wheel and see that the wire is in place, not damaged, and plugged into the harness. There is a wire lead about 18inches long and a plug into harness up by the running lights. ...... third sensor is on top of the rear axle and held in by one 5-6 mm bolt......... harness plugs into the sensor. ......... since the light is on all the time, you have an open circuit / failed sensor.