Hey all, had a question regarding some peculiar engine behavior.

For a couple of months now, I've noticed that for a relatively small RPM range, my engine does not behave well. In the 1650-1850 range, the engine shudders and just feels poor. It is particularly bad because that is the general RPM range on the highway in 5th gear when traffic/police limit my speed to below 75 mph.

I've been told it could be a valve that is bent slightly and is excited at those RPM's or potentially some exhaust damage/age that is making more back pressure than normal for that engine range.

I know that's a fairly vague description of the problem, but I'm hoping someone else has had a similar experience. Thanks in advance!

Car Specs:
Stock 2003 Mustang GT
4.6L V8 5-Speed Manual Trans
~110k miles

 

Does it feel like a misdire? I've had bad cops that caused misfires down low but at wot behaved fine and vice versa

 

It doesn't feel like a reduction in power or a skip like a misfire. It's much more of just a rough section of RPM.

 

The Exhaust Gas Recirculation (EGR) system can create this problem when the EGR valve sticks and/or gets sluggish--my '03 began exhibiting the same symptoms at about 98k miles--being cheap and lazy I just disabled the EGR in the tune...

 

I'll check it out, thanks cliffyk!