[RESOLVED] turbo spools but wont boost and wont rev over 4000rpms

[dsm1gawdfox]

i have a 1990 gsx that i recently swapped a 91-94 ecu into. when i start my car it starts right up and idles at 1000-1100rpms(normal before ecu swap) car runs with no boost at all up to 4000rpms and wont rev any farther. it feels like its hitting fuel cut or rev limiter. i have done a boost leak test and found only a small leak in my throttle body(tb shaft seals) but its not big enough to cause this problem. i checked my wastgate and wastegate actuator and they are working normally. there is no shaft play and the turbin spins freely. this car is almost bone stock. i have a 2gmaf that is good. i also have 3inch turboback exhaust no cat. i have a walboro 255 fuel pump rewired. i have checked all of the ignition components and they are all good. i am stuck please help

 

[My1GLaser]

Wires 6&14 need switched at the ECU when using a 90 ECU in a 91-94 or vice versa. http://www.dsmlink.com/images/forums/1GECUPinout.pdf

 

[dsm1gawdfox]

the wires are switched sorry i forgot to mention that. by the way when the wires are not switched the car will start and idle fine but when you step on the gas the motor will just bog down.

 

[ROOKIE1]

Fuel pressure regulator since you are running a 255 .

 

[dsm1gawdfox]

before the ecu burned out the car ran great with stock fpr. along the lines of fuel, i have also checked my injectors so they are no the problem.

 

[ROOKIE1]

Rear bumper black by exhaust ? To much fuel is what I am saying . Bogging or over running injectors with larger pump .

 

[dsm1gawdfox]

i bought the car with the pump in it and it ran awesome up until the day my ecu fried then i swapped in the 91-94 ecu and now i have this problem.

 

[ROOKIE1]

Are you sure the 2g maf was wired correctly ? Sure the correct pin outs were swapped on the ecu ? What pressure on Boost leak test did it hold ? The more pressure to system the larger/faster it leaks .

 

[dsm1gawdfox]

boost leak tested at 20psi took a while for leak all the way down through tb shaft seals
2g maf is wired correctly and ecu was wired correctly.

 

[My1GLaser]

Why/how did the ECU fry? Maybe something else was damaged during the incident that fried the ECU. What are you using for tuning? Do you have a datalog of the car running to verify the hz reading of the MAS?

What is the condition of the new ECU? Were the caps replaced? Did you look at the board for caps leakage residue or burnt tracks?

 

[dsm1gawdfox]

the 2g maf working i tried it on my brothers car to check it and it is reading properly. the ecu is good as well it was from my buddies car he took it out the day i put it in my car becuase he got an eprom ecu but just to double check it we put it back in his car and his car ran great. my old ecu fried because the caps leaked all over the place.

 

[92awddsm]

the 2g maf working i tried it on my brothers car to check it and it is reading properly. the ecu is good as well it was from my buddies car he took it out the day i put it in my car becuase he got an eprom ecu but just to double check it we put it back in his car and his car ran great. my old ecu fried because the caps leaked all over the place.

Sounds to me like you are running a 2g maf with no afc or other compensation for increased airflow.

 

[dsm1gawdfox]

i put my stock maf back on and i am still having this problem, so that rules out the maf all together

 

[dsm1gawdfox]

problem solved i took off the exhaust manifold and found a large piece a metal from who knows where in the turbo housing plus the wastegate housing is cracked all the way threw. all this means is yay new turbo awesome. i have pics included