Runs well for ten minutes then has a significant loss of power

1991 PONTIAC FIREBIRD
70,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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RYDALC912
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my car will run just fine for a little bit after start up but after i drive it for a little bit the check engine light comes on and the engine sounds and smells like its running too rich.
Mar 20, 2020 at 12:58 PM
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ASEMASTER6371
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Good afternoon,

Do you know the code? It sounds like when it goes into closed loop, it is running rich.

A common issue is the MAP sensor but before you go there, I need the code and you need to check the hose from the sensor to the throttle body and be sure there are no holes in the hose.

Roy
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Mar 20, 2020 at 1:12 PM
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TOUGHDIVER
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  • 224 POSTS
Hi,

It could be the engine coolant temperature sensor is giving false reading the readings can be checked with a scan tool. I'm attaching sensor location and repair guides below. Let us know it you need more information.

https://www.2carpros.com/articles/symptoms-of-a-bad-coolant-temperature-sensor

Thanks
Joe T.
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Mar 20, 2020 at 1:23 PM
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