kodyps

I drive a 93 f250 with the 5.8.

I just replaced the fuel filter, she drove fine for half an hour, and now I'm back to square one.

The Rpms go up and down while I idle, and it is sloppy until I reach 3rd gear.

I know there are many things that could be wrong, but does this sound like anything specific? I tried to run codes but the light never started to blink.

I've noticed some Hoses under the good are cracked, could it be a vacuum leak?

It seems to run okay with a cold engine, then as it heats up after a drive is when it becomes problematic.

Crowder

I'd start by replacing those old cracked lines. And cleaning the throttle body. And make sure you're pulling codes correctly. And of course make sure the bulb works lol

fltdriver

Use a voltmeter (analog) to get the codes, do what crowder suggested, since you have the voltmeter out test your TPS and IAC to ensure proper voltage. My guess would be vacuum lines or a wire grounding out on TPS (if it's not bad).

kodyps

All of these lines are very dry. What lines are they? The one that goes to the throttle body is very cracked.

tanman90

Those lines come from the vapor canister. It runs the fuel vapor from the gas tank into the intake instead of into the atmosphere.

Chris_1

iTrader: (1)

Check the things mentioned, check the fuel pressure regulator hose for a fuel smell (bad), and now that you've changed the fuel filter get some injector cleaner in the tank to try and flush the injectors out. If you have access to a fuel pressure gauge, check that too. You should have 35 to 45 psi KOEO. Less than 35 causes problems