i recently purchased a 92 gsx.....it runs good no smoke or anything......but it wont rev past 5400 rpm.....it also surges at idle when it is cold.........any ideas on what might be wrong would be appreciated

i was also wondering what the boost stock should be......as far as i can see everything controling the turbo boost appears stock......but before it cuts out at 5400 grrr......according to the stock boost gauge it is pulling nearly 14psi......that seems high.....thanks for any help!!!

 

can you get a pic of the engine bay. I bet you have a MBC. And are you saying that while you are under full throttle and hit 5400rpms the car just dies. Cuz that would be fuel cut most likely. And the idle surgeis ussually because of an air leak somewhere in the intake manifold. Or a bad sensor.

 

the stock guage is 100% inacurate, dont trust it at all. on my GSX mine always says about 10 psi weather im boosting 6 or 18. I would check for boost leaks or holes in the hose to the wastgate actuator if its all stock stuff.

 

sounds like the exact same thing i had happening with my car, im gussing you have a boost leak. check all of your piping make sure the clamps are tight, look for any holes like racerx55 said. what was happening with my car is the half of the rubber gromit above the intercooler was torn off-wtf?- and my car wouldn't rev above 4800, it was pretty much undriveable oh and it was always showing me boosting at my max.once i fixed it my car ran great

 

i cant figure out how to get the pictures to upload.....grrrr......what is mbc

 

MBC = Manual Boost Controller

 

if you ever have a question as to what something might mean then go to this thread and you should find it, if you dont let us know so we can add it https://mitsubishiforum.com/m_83436/tm.htm

 

i have a service manual...everything as far as boost control looks stock....if 5400rpm is fuel cut off what are some options to raise it.....the car feels like it needs to rev higher....its is still pushing you back in the seat when it cuts off......where can i hook my auto meter tach in at.....what the book says wont work


P.S. Thanks for all the help......and any new ideas

 

fuel cut is not something that you raise or anything. It is a safety measure when your either maxing out your fuel pump, injectors, or running too rich. Something along those lines and the computer cuts the engine to prevent damage to the engine. Could you maybe be misfiring? Bad plugs and wires? Most likely though its fuel cut because of your air leak that you probably have. If you have a leak then your car will meter the air, then compensate with fuel, problem is the air that it meters leaked so now you have too much fuel...hence fuel cut.

And to wire the autometer tach you should know which wire is which so power and ground are simple. But the tach wire you hook up to the ignition pulse from the ECU. Its usually a solid white wire i believe. Just go to http://www.vfaq.com/index-main.htmland then electrical and 1g pinouts, it will show exactly which wire it is

 

thanks for all the help.....i will check these things out and see what i got......hope they fix it....lol