10-05-2023, 08:55 PM
that ECU looks new. to me, not 28 years old. caps look fresh, not even dust there. wow.
im thinking dirty injectors, try Techron fuel injector cleaner in the tank, run it see if it cleans out.
yes ,I had XJ jeeps from 88 to 99, even new ones,
running rich.
fuel pressure at 36psi keyon, and idle 30psi. it drops PSI.
then key off and pressure holds, leak down test, holds over 25psi for one minute, if not injector leaks or the check ball valve in tank pump is bad.
there is and injector balance test that is not easy to do DIY.
best is get the injector set clean, in shops that do reverse flow ultra sonic cleaning, the injectors have 10micron screens, so....
http://fixkick.com/INJECTORS/PUMP/reg-graph-mpi-g.jpg
measure pressure at the RAIL.
im thinking dirty injectors, try Techron fuel injector cleaner in the tank, run it see if it cleans out.
yes ,I had XJ jeeps from 88 to 99, even new ones,
running rich.
fuel pressure at 36psi keyon, and idle 30psi. it drops PSI.
then key off and pressure holds, leak down test, holds over 25psi for one minute, if not injector leaks or the check ball valve in tank pump is bad.
there is and injector balance test that is not easy to do DIY.
best is get the injector set clean, in shops that do reverse flow ultra sonic cleaning, the injectors have 10micron screens, so....
http://fixkick.com/INJECTORS/PUMP/reg-graph-mpi-g.jpg
measure pressure at the RAIL.
http://www.fixkick.com