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P0103 with speed density tune,stumbles at partial load

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Old Feb 14, 2020 | 08:17 AM
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Default P0103 with speed density tune,stumbles at partial load

So my daily driver 98 Trans Am started stumbling at partial load like on the interstate or anytime it would go into lower rpms under 2000 rpm.Its intermittent & will sometimes go away under load,the rpms pick up & the stumbling stops but comes right back after the rpms drop down again.Been happening for about a week now.When checking for dtc's it had a P0103,but when I had my tune done the MAF wasnt working so the tuner gave it a speed density tune.That has worked for 6 months with no problems until recently.The car has 145k on it,AT,long tubes,lid,oil catch can ,SLP loudmouth and the tune.All those parts have been on for 6 months.For all I know the 103 code may have been there the whole time?Ive never scanned it until now.It has always ran fine so I didnt see a need to scan it.The engine light never came on also.
Any ideas?
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Old Feb 14, 2020 | 10:15 AM
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I spoke with my new tuner who did my h/c SS(did a hell of a job btw)We decided were going to add the MAF back into the tune & see if that corrects it.The P0103 code will remain there but the ses light has been turned of for that code.If this fixes Ill update be sure to update thread.The problem started when the colder weather came with monsoon rains then switched back to warm again,then back to cold.Virginia weather at its finest!Ill know tomorrow if we fix it.
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Old Feb 14, 2020 | 12:42 PM
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So it ran fine for 6 months, started running poorly and your tuner wants to put a MAF on it to see if that fixes it?

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Old Feb 14, 2020 | 12:53 PM
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If you dont have a MAF, that code has always been there. That's how the PCM knows to go speed density
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Old Feb 14, 2020 | 03:07 PM
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Originally Posted by LilJayV10
So it ran fine for 6 months, started running poorly and your tuner wants to put a MAF on it to see if that fixes it?
we will look at the data first of course.Ill be sure to update what we find.
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Old Feb 14, 2020 | 04:42 PM
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Originally Posted by HATEDBIRD
we will look at the data first of course.Ill be sure to update what we find.
That's good to hear.

If not, you need to find a new tuner.
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