the standardization of the 2.6-liter engine for 1992
low engine power has over 50 causes.
with bad fuel, the job gets harder.
the ECU can not inject correctly with clogged injectors, or low fuel pressure, (fuel filter new/)?????
new spark plugs yet> be the time, no ?
ill look up your engine now in, Mitchells (so can you)
and see what you have, Isuzu rand carbs here until 1994.
so.....
the engine is the 4ZE1 engine.
looks like its not TBI but the MPI engine with 4 injectors.
so is the fuel pressure, at spec> (a gauge does that)
spec it below, 35psi,
so engine good? compression, its old.
spark good, do the tuneup yet.
then fueling. is next and last.
bad fuel, is bad fuel. and causes collateral damage.
new fuel filter yet>?
and what came out of the oil filter. clean fuel or what?
sludge, slime, dust , rust, or clean fuel smelled good.??????
this engine runs off a MAP sensor, on the top center right fender.
the vacuum line to it must be good, and have normal vacuum to it.
the engine has no OBD2 scanners.
its OBD1 that year, in USA> and you;d first check all fuses.
then see that the CEL lamp glows key on, than goes out running
if it goes out running ok, but if not, its best no matter what to
do the ISUZU flash codes (DTC errors) first.
(this works on all cars EFI up to 1995)
tuneup spec, page. , gap, timing , PSI pump, rpm. and lash.