While driving the RPMs drop down

1994 FORD F-150
160,000 MILES • 5.0L • V8 • 2WD • MANUAL
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JASON UNDERWOOD
  • MEMBER
  • 1 POST
While idling and while driving, the engine will rev to 3,000-3,500 RPMs, then drop down to almost stalling. I disconnected the MAP sensor while idling, and things calmed back down, but as soon as I reconnect it, everything goes crazy again. If I let the truck sit for a few days, I can drive it for about 10 minutes before it starts acting up again.
Apr 8, 2022 at 4:14 AM
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JACOBANDNICKOLAS
  • ✓Experienced Mechanic
  • 110,240 POSTS
Hi Jason,

That certainly doesn't sound safe. LOL Here is what I need you to do: We need to know if there are any diagnostic trouble codes stored. The truck has an OBD1 system and doesn't require a scanner to get codes. Follow the directions in this link and let me know the results:

https://www.2carpros.com/articles/ford-lincoln-mercury-obd1-1995-and-earlier-diagnostic-trouble-code-definition-and-retrieval

I attached a pic below to help you locate the connector.

Let me know what you find.

Take care,

Joe

See pic below.
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Apr 8, 2022 at 1:19 PM
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