2001 S Type 3.0L 44K miles. Mostly city driving below 50MPH.
The engine stutters/cuts out severely at various speeds it seems just before it downshifts to a lower gear to pull an incline in the road. Make sense??
Example: Cruising city street at @ 45MPH. Start up a hill, holding accelerator at a steady 45, the engine starts stuttering.
Example: Cruising an interstate highway at @70MPH. Start up an incline, and just before I feel it start to switch to a lower gear to pull the hill, it starts stuttering/missing. No warning lights on dash. New fuel pump.
Almost like, at the point where the load on the engine requires a transmission downshift, the engine starts misfiring. Stomp the accelerator and it immediately responds.
Any ideas? Thx., Mack

 

Sounds like you're starting to lose a coil. do a code check of the ecm and hopefully there is one stored. replace that coil if its the left bank or all three if its the right bank. that's my suggestion.

 

Seconded on the coil suggestion - had exactly the same problems three years back. All the coils in the driver's side can be replaced by you very easily provided you carefully unplug the electrical connectors (which become very brittle) and then unscrew the one retaining bolt per coil. It takes about a couple of minutes to remove and replace each one.

Cost for three coils is $75 - $150 (depending where you buy them), so it's worth the gamble if you can't do a code check. I wish I'd known more and done this the first time a coil went, as the cost of the shop checking the coils and replacing the one that was faulty was also approx $150!

Replacing all three on the right bank (passenger side) as Mark suggests is great advice, as you don't want to have to do that twice (or pay a shop to do it twice). I did it myself and passed an enjoyable few hours doing it, as it's fairly straightforward and doesn't require any specialist tools. Unfortunately, I was without a camera at the time and took no pictures.

Cheers,

Tim