OK, so here's the deal.

I have a NEW motor. It's the LDK!

The 1st blew up because of a bad turbo, i think. The 1st motor always had sputtering at full throttle, before AND after HP tune by Term2. I tinkered with parts, hoses, etc. Sometimes it would pull hard with no issues and sometimes it would just sputter at full throttle. But I dealt with it by going 90% in most gears and gritting my teeth.

The vehicle became a daily driver for wife, then daughter, then son and, since they never pushed the car hard, no issues.

14 years and 160k miles later, I allowed a garage start up to rebuild the head and, right after, the turbo blew up and killed the whole engine. Did the mechanic mess something up? Not sure.

So he put in a brand new LDK motor ... and guess what, same sputtering issues as with motor #1. I am not happy. I thought buying a new motor would, at least, solve the sputtering issue!

I'm convinced it's a bug in the computer as I've tried everything else and the old computer was swapped in with the new motor.

What do you guys think?

 

If the "sputtering" was happening before you tuned you should have mentioned that to your tuner and you should have fixed that issue before tuning. Since it happened before you tuned doubt its tuning related.

The LNF/LDK are pretty finicky when it comes to spark plugs and sensors. I would suggest checking your spark plugs for proper gaps. The OEM plugs ACDelco 41-108's are the plug of choice for the the LNF. I'm not sure about the LDK. Also take a look at the upstream o2 sensor. That sensor is the stock wideband sensor in our car. A couple years ago, the screen inside of my o2 sensor chipped, and my car developed sputter or hesitation. Mine was noticeable at 3500 rpms in lower gears, and higher rpms in higher gears.

Also you really get your ECU retuned for the LDK. Using a 16 y/o tune for LNF on the LDK is not helping you right now.