brief hesitation at highway speed

[RickHaleParker]

When was the last time you cleaned the MAF sensor?
It sounds like it is getting the wrong Air/Fuel ratio when you step down and takes a few seconds to recover and get it right.

[darylrobert]

did you order the Porsche TCV?..i would be interested if there is real actual improvements

[hu5ker555]

It's probably been a year or two since I cleaned the MAF. Will give it a try.

[hu5ker555]

Update...so I've replaced fuel filter and fuel pressure sensor with new parts. Cleaned the MAF. Swapped out the TCV and PEM with junkyard items. Still not fixed...brief hesitation/stumble that occurs in the 50-60mph range while lightly accelerating.

I don't have VIDA/DICE so not sure where to go next. Maybe try a new set of coil packs? Just seems odd that they would only act up in the 50-60 mph range while accelerating, but work just fine all other times and with no fault codes. Idles and runs otherwise like a champ, though the turbo feels a little weaker than what I remember. Still cruises at 80mph without issue.

[RickHaleParker]

I don't have VIDA/DICE so not sure where to go next.

You don't need DiCE to use VIDA. Any J2534 interface will work for diagnostic. You can get a J2534 interface for a little as $36.00.
I use a Mongoose JRL Pro V159 interface. $36.00 is probably just a fraction of what you will throw at it without a proper diagnostic. There are instructions on MVS that will on how to get VIDA and install it.

If you have any J2534 interfaces, install VIDA and try it with the J2534 interface. Got a friend with a J2534 interface ... borrow it and install the drivers, VIDA should detect it.

[abscate]

How many miles on the spark plugs? Try those before coils

[RickHaleParker]

Engine hesitation is most likely a fuel/air mixture that is too lean not fire. Look for air leaks. Think about Injectors if they have lot of miles on them. Coils and plugs misfire not hesitate.

[hu5ker555]

Ya, it seemed logical to me that it would be more of a fuel/air delivery thing, which is why I first tried the fuel filter, pressure sensor, and TCV, and PEM.

I might try new plugs and coils next. Over the years, I've swapped out one or two when they failed so maybe a completely new set will freshen things up.

If that fails, I guess injectors would be next in line. To my knowledge, they are original. 204k and probably overdue.

[RickHaleParker]

If that fails, I guess injectors would be next in line.

Check for air leaks. A smoke test would be the best way. You can try spraying starting fluid around the intake. A leak will suck in the starting fluid and you will hear the engine surge.

[ignatz]

Plugs.