Edshea

A little over 2 weeks ago I (aka classic truck nube) purchased a Ford F-150 XLT Lariat 4x4 302 5.0 manual transmission with 131K. The truck is in excellent condition inside and out and has been well cared for.

The truck has no modifications. I've only replaced the rotor and a new standard exhaust.

Issue:
While driving around town the engine will intermittently cut out (shut off). No coughing, gadping or sputtering - it just stops ruining. I depress the clutch, turn the key and it restarts normally - no grinding or hesitation. I may drive it 20 miles without an instance... or I may drive it 2 miles and occurs twice. Instances don't happen at any repeatable instance. It's happened while idling at a light, cruising at 50 mph, or coming to a stop. It happens cold or hot.


A cursory internet search comes up with a wide range of options.

Any thoughts would be appreciated. Thanks

Steve83

Click this, read the caption, & follow the link in it:


(phone app link)

Read the applicable diagnostic procedure Ch.5 (usually Sec.5 or 7, depending on edition), collect all the tools mentioned, and keep them in the truck WITH the manual. When the fault appears, begin diagnosis immediately. If the fault disappears, keep driving until it reappears & start over. Eventually, you'll make it to a diagnostic step that identifies the fault. Then you can repair it.

If it turns out NOT to be an ignition system fault, read the Troubleshooting chapter (before Ch.1), and keep a variety of tools & testers in the truck: fuel pressure gauge, timing light, DMM, 12V test light...

raski

Your situation will be difficult to troubleshoot since it restarts everytime. The way the engine dies without sputtering would steer me towards electrical/ ignition. There have been issues with the pickup coils in the distributor and the distributor mounted TFI ignition module which you likely have. Use only Motorcraft parts for this. From what I understand some early 87's may have the old fender mounted module . If you cannot effectively troubleshoot (which I favor usually) I would try those and hope you nailed it.You are not looking at a lot of money and may be less than a tow should it finally quit 20 miles from home.