Engine misfiring, backfiring and will not stay running at idle

1994 FORD MUSTANG
150,000 MILES • V8 • 2WD • MANUAL
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DARRELL EDWARDS
  • MEMBER
  • 1 POST
What would cause my car listed above gt with a 5.0 302 engine 4 and barrel carburetor to skip, lose power when you accelerate and going down the road, won't stay running while idling and backfiring. I just recently replaced the head gaskets intake manifold and gasket distributor cap and rotor button also the carburetor as well.
Mar 18, 2021 at 2:01 PM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Good morning,

I do not see anything about replacing the plugs. If they are not working correctly, it will misfire and stall.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

https://www.2carpros.com/articles/how-to-change-spark-plugs

I would get a vacuum gauge and check the vacuum while the engine is running and at idle. You need 18-20 inches of steady vacuum. The backfiring concerns me as it could be valve related.

https://www.2carpros.com/articles/engine-backfires-while-running

Roy
Mar 18, 2021 at 6:58 PM
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