In the few months that I have owned my S4 TII it has had a weird problem since I got it. Very randomly the car will sort of sputter or cut out then it will be fine and I am stumped. Its not fuel cut because it some times happnes while im not boosting like taking off slowly from a light or yesterday it did it for a few sec cruising down the freeway in 5th gear. Some times it will do it while boosting which i dont like I have changed the fuel filter and looked at the one in the tank and it seems fine. the only other thing I can think of is maybe a coil going out??? bad plug wires?? maybe a ground? any advise at this point would help im getting frusterated.

 

no one???

 

You could have a worn out TPS resistor.
-To test:
Unplug the TPS connector.
Clip a cheap analog (needle type) VOM on the green & orange pins.
Set it to the 1K scale.
Hold off the throttle & work the short range TPS plunger in & out.
You should see a smooth sweep from ~0 to ~5K ohms.
Any bad spots or drop outs in the stroke - it's bad & will give RANDOM FUEL CUTS at part throttle.
(Before you toss it, try spray contact cleaner between the sleeve & plunger.)
- Then set it:
Find the fast idle (warm-up) cam & back it off so the throttle sits on the hard idle stop.
Adjust the setting to 1K ohms.
While holding off the fast idle cam, open & close the throttle a few time to see that the 1K setting repeats.