I have swapped a Turbo into a 89. Change engine,tranny,ecu,fuel pump,maf,sensor
Idles great revs up great. When I drive it 1st gear pulls good and runs great but when go to 2nd and up it sputtters like bad plugs and then even when I go to1st again runs like crap. If I shut it off the whole process starts over again. I checked for ecu codes but none a present. Any suggestions would be greatly appreciated.

 

How much boost are you running when it sputters?

 

In 1st gear I build up to 8lbs then when I shift to 2nd it starts to build boost (a lb or two) then it shuts down and starts to sputter. I do have a blow off on it but I don't think that matters.

 

It sounds like you are passing 8.6 PSI, at which point the ECU will cut fuel to the rear rotor.

 

How do it limit it to 8?

 

Boost pressure is limited by the wastegate. Stock wastegates don't flow all that well, and free-flowing exhausts/intakes can lead to boost creep. http://fc3spro.com/TECH/HOWTO/KWG/kwg.html

But if you're only building 1-2 psi total before it sputters, that wouldn't be fuel cut. If you're building 1-2 psi more than in 1st gear, I would say it is fuel cut.

Are you getting any trouble codes (check engine light)? http://www.johnr.com/cpucodes.html

 

It does sound like fuel cut due to high boost. I didn't know it had a 8.6 limit. I really appreciate all the help and suggestions. I won't be able to try it for a couple of weeks but I will post the outcome. Thanks again