Low rpm stumble

GhostDog

New Member
Jul 20, 2019
2
0
1
48060
Hesitates and stumbles below 2 k rpm
Fine at idle fine in neutral fine aboce 2k
Changed tps made it worse
Cleaned maf no change
Trying coil next
Then going plugs/wires
Any help appreciated pulling my hair out
99 3.8 v6 mustang
 
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In the interest of being through don't overlook the role that a bad alternator diode could play in problems such as this.

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Given the relatively low price of spark plugs why not do them as well? This will give a chance to perform a visual inspection of the spark plugs which gives a good indication of combustion efficiency. This also offers an easy way to look for things like anti-freeze in the combustion chamber.