For starters, not using 93 octane gasoline in any diamante can sometimes cause hesitation and/or diminished performance. People who are penny wise and pound foolish often ignore this recommendation in the owner's manual.
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Check your spark plugs and wires. If that's not it, try the mass airflow sensor.
~Pengauin
We replaced the $75.00 electric Throttle Pedal controler Sensor to correct the same problem, ours apparently wore out and kept hesitating when we tried to accelerate.
hope this might help-wtb89
mine had that problem and i changed the rotor and rotor cap and it stoped so you should check the ignition system
does a 1999 mitsubishi diamante with a 3.5 engine have a non interfrence engine
Make and model please 1992 Mitsubishi diamante
Engine Control Module.............
all mitsu diamante are 3.5 6 cyl
Where the bottom radiator hose connects to the engine
Time for a tune up.
My owner's manual recommends 5w 30
Likely if it's the same engine, but best ask a mitsu dealership, they can compare part numbers
Think you might have to take off the intake manifold, it a process
It is near the junction of the engine and the auto tranny. it will have a spade plug and a larger battery connection on it.
It is important to have a well working car while on the road. The lack of fuel getting to the engine would cause hesitation on acceleration,
Look at the lower end of the engine - try to follow the + battery cable