MPFit

Yes sorry- yesterday I warmed up. No KOEO codes. KOER codes 21 and 52.
My power steering pressure switch his disconnected so I expect code 52. Code 21 I believe is VREF for ECT is out if self test range. Back probing and resistance testing on the sensor seem fine. Voltage test with the key on engine off was 4.8 V.
Tried to start this morning, it starts and stalls a few times before it starts completely and sputters from cold.
Im leaning towards an ignition system problem.

redrock

Please back up to the time you first noticed this condition.

Did it cause you to take action, or was it the result of doing some maintenance?

Bob

MPFit

No, it started after a car wash- I let it dry out, and drained tank / ran through 3 tanks since. Not sure if timing was or wasn’t due to getting wet. I’ve ran some ignition diagnostics and found a problem in the actual Spout circuit- more specifically no continuity in the wire, and lack of power to spout during start and running conditions. No resistance between spout and EEC Pin 36- I will replace the wire as soon as I can and remeasure to make sure I’ve got the ignition taken care of. Then thermostat and ECT (which is throwing a code but testing fine).
i have never gotten a Spout code; and when purchased truck no Spout connector was present for whatever reason.. maybe previous owner knew it had a problem and tried to hide it to sell? Not sure..

redrock

Hard to believe all your trouble reared its head after a car wash. The 4.9L engine was a great workhorse engine for Ford.

MPFit

raski

I would go with the obvious, investigate why you have that code 21. I have an 87(4.9) which should be the same as your 89. Your VREF is between 4 and 6 volts which is good. Verify again your resistance of your ECT sensor at the following temperatures. 50 degrees=58,750 ohms, 65 degrees=40,500 ohms, 180 degrees=3600 ohms and 220 degrees=1840 ohms. If those check out OK, check for continuity and shorts from the ECT to your processor. At the processor connector, pin 7 is your ECT signal and pin 46 is your signal return. There is also a large connector coupling the wiring from the engine compartment to inside the cab. I believe it is under the master cylinder. Make sure it isn't corroded up. If the wiring is intact and no shorts, I would be taking a good look at that processor. New doesn't mean a whole lot when it comes to electronics. Do make sure when you start checking wiring making resistance checks or removing the processor connector, remove your negative off the battery first. Hope this helps.

PissJugsMac

Hi. I was wondering if you could help. I have a 1989 f150 lariat xlt 5.0. Its developed a problem over the past week. When u first start up and tk off it will cut out pretty bad. No smoke that I noticed (black smoke). It seems to get a bit better once it warms up but still cuts out just not as often. Any idea what could be going on? I got a new fuel filter but haven't yet installed it. I'm just trying to get as much info as I can in case its not the filter. My luck....it won't be the filter. Plus and wires aren't that old I dont think. The way it cuts out while giving gas, I feel like could hurt the transmission. Thanks for any/all help you can poss give. Have a great day.

-PissJugs

PS
Its a 4 speed manual btw....

raski

Make sure you have 30-45 psi of fuel pressure off the fuel rail.

You should try starting a new thread for your problem.