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Jamesbajaboss 09-21-2020 04:41 PM

454 MPI intake
 
Hello, Guys
1997 454 MPI Mag.VI starts right up but after warm up it starts sucking inn to much air(its how it sounds) and shuts down, starts up again same thing but in less time it shut down if you try to open throttle shuts down as well it happen all of sudden any advise
or heads up in what needs to be check ?
Thank you

Trash 09-21-2020 08:05 PM


Originally Posted by Jamesbajaboss (Post 4758221)
Hello, Guys
1997 454 MPI Mag.VI starts right up but after warm up it starts sucking inn to much air(its how it sounds) and shuts down, starts up again same thing but in less time it shut down if you try to open throttle shuts down as well it happen all of sudden any advise
or heads up in what needs to be check ?
Thank you

Check fuel pressure and for signs of vapor lock.

Griff 09-22-2020 01:07 AM

Sounds like vapor lock. Common problem when the engines are hot and then turned off for 30mins to a few hours.
High heat, humidity and ethanol fuel all make vapor lock happen more easily.

Tractionless 10-02-2020 09:04 AM


Originally Posted by Jamesbajaboss (Post 4758221)
Hello, Guys
1997 454 MPI Mag.VI starts right up but after warm up it starts sucking inn to much air(its how it sounds) and shuts down, starts up again same thing but in less time it shut down if you try to open throttle shuts down as well it happen all of sudden any advise
or heads up in what needs to be check ?
Thank you

Sounds like the IAC is opening too much. Remove and see if it's broken in pieces. If not you want to datalog and check the steps, you shouldn't be over 40. If so the IAC may be bad and/or IAC driver in the ECU may be bad.


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