Ok, just got my bargain basement (sitting for 3 years) 1999 5.4 4x4 running... Had to replace the fuel pump.

So, I have two issues.

1. Rough idle and running. When gas is hit it has a major hesitation.
2. Brake peddle likes to stay on the floor. The brakes actually work, but the peddle has no kick back really. Brakes stay engaged unless you lift the peddle with your foot.

So, on the rough running, I have purchased spark plugs. How do I test the coil packs? Is there a simple ohms test?

On the brakes, I am thinking master cylinder and will be doing the following test.
1999 F150/250 Workshop ManualBrake Master Cylinder
Normal Conditions

The following conditions are considered normal and are not indications that the brake master cylinder (2140) is in need of repair.
Condition 1: During normal operation of the brake master cylinder, the fluid level in the brake master cylinder reservoir (2K478) will rise during brake application and fall during release. The net fluid level (after brake application and release) will remain unchanged.
Condition 2: A trace of brake fluid will exist on the booster shell below the master cylinder mounting flange. This results from the normal lubricating action of the master cylinder bore and seal.
Condition 3: Fluid level will decrease with pad wear.
Abnormal Conditions

Changes in brake pedal feel or travel are indicators that something could be wrong in the brake system. Refer to the Symptom Chart for abnormal condition diagnosis.
Bypass Condition Test

To perform this test:

1. Disconnect the brake lines at the brake master cylinder.

1. Plug the outlet ports of the brake master cylinder.

1. Apply the brakes. If brake pedal height cannot be maintained, the brake master cylinder has an internal leak and must be rebuilt or a new master cylinder installed.

Compensator Port Check

The purpose of the compensator ports in the brake master cylinder is to supply any additional brake fluid required by the system due to brake pad (2001) wear and to allow brake fluid returning from the brake lines to the brake master cylinder to enter the brake master cylinder reservoir.
The returning brake fluid will cause a slight turbulence in the brake master cylinder reservoir. Turbulence seen in the brake master cylinder reservoir upon release of the brake pedal is normal and shows that the compensating ports are not plugged.


Thanks!

 

is it throwing and check engine codes? That's the first place to start in diagnosing your problems. As for the brake pedal issue I've never heard of that before but would imagine you would be looking at the master cylinder as the culprit.

 

Ok, thanks! Got the ODBII tester tonight from Autozone and will be pulling the codes (if they are present) tonight or tomorrow.

Truck was sitting with no battery for quite some time so, I am unsure if the codes will be present yet. I only had the truck running for a little while. Does the PC take a little while to throw a code or can it be immediate? Guess I will find out soon enough.

 

Its almost immediate, try bleeding your brakes, and check the pad to make sure they still have wear. As for your engine check for codes if not, it might just need a good tune up.

 

Thanks for the suggestions... This thing was sitting for 3 years. Is that likely to cause either of the following?

1. air in the brake system?
2. Seals dry up and break in the master cylinder.


Right now I am pointing towards 2 but would like opinions.