2004 3.9L V6 Weird hiccup when accelerating

[Doffey01]

My mustang has this weird hiccup where it feels like it jolts back and forth like a bad shift when im accelerating sometimes. It does this enough to be noticeable but not in regular patterns. Its all stock under with 95k miles and a 4 speed auto. Thanks if you can help

 

[wmburns]

It would help to know what else is occurring with the PCM and sensors at the time. How to find this information? A good way is with a graphing ODB2 scanner that is capable of monitoring and saving key data over time.

Here's some information on an affordable Windows based unit that can acquire the key information.

ForScan ODB2 scanner w ELM327 USB
https://www.stangnet.com/mustang-forums/resources/forscan-odb2-scanner-w-elm327-usb.57/

The other way to do this is to rule out various "possible" items. For example:

• excessive EGR flow
• low fuel pressure
• incorrect sensor input such as ECT, IAT, FRPS, shift solenoid.