Why won't my 1990 acura integra go over 4000 rpm?

1) Turn on all electric systems- AC/wipers/radio/lights etc

2) if car stalls randomly at low RPM - Replace the Alternator
These cars are very sensitive to fluctuations in voltage and it will stall.

please go buy a Haynes manual.
Acura Parts AcuraOEMparts com Genuine Acura OEM Parts from Delray Acura

Most common issue is a bad ground

On this website you find fuse box diagram and description for Acura Integra (1990)

Acura Integra 1990 wiring diagrams fuse panel CARKNOWLEDGE

1990-1991 OBD0*
Engine: B18A
Cylinder Arrangement: Inline 4 Cylinders, Transverse
Type: Water cooled, 1.8L, 4 cylinder, 16 valve, DOHC
Displacement: 111.9 cu in (1834 cc)
Bore & Stroke: 3.19 in x 3.50 in (81mm x 89mm)
Compression Ratio: 9.2 : 1
Valve Train: Double Overhead Camshafts, Belt Driven
Fuel System: Programmed Fuel Injection (PGM-FI)
Horsepower: 130 hp @ 6000 rpm
Torque: 121 lbs.-ft. (16.8 kg-m) @ 5000 rpm
Redline: 6500 RPMs
Engline Block: Aluminum Alloy with Cast Iron Cylinder Liners
Cylinder Head: Aluminum Alloy

YOU NEED TO CONNECT A TACHOMETER ACCORDING TO THE MANUFACTURERS INSTRUCTION.ON THE 1990 - 1993 MODELS USING A SUITABLE JUMPER WIRE CONNECT THE GREEN AND BROWN TERMINALS OF THE IGNITION TIMING ADJUSTING CONNECTOR LIGHT GRAY WIRE LOCATED UNDER THE RIGHT SIDE OF THE DASH.MAKE SURE ALL WIRES CLEAR OF THE COOLING FAN AND HOT EXHAUST MANIFOLDS.START THE ENGINE POINT THE TIMING LIGHT AT THE TIMING MARK POINTER AND THE CRANKSHAFT PULLEY.ON THE 1990 - 1993 MODELS THE POINTER SHOULD BE ON THE RED MARK 16 DEGREES BTDC ON THE CRANKSHAFT PULLEY AT 700 - 800 RPM.IF NECESSARY ADJUST THE TIMING BY LOOSENING THE DISTRIBUTOR ADJUSTING BOLTSSLOWLY ROTATE THE DISTRIBUTOR IN THE REQUIRED DIRECTION WHILE OBSERVING THE TIMING MARKS.AFTER MAKING THE NECESSARY ADJUSTMENT TIGHTEN THE HOLD DOWN BOLTS TAKING CARE NOT TO DISTURB THE ADJUSTMENT.REMOVE THE JUMPER WIRE.

have fun

Easiest way to do this is go to a junkyard and take one off another car. shouldn't cost more than a couple dollars. You won't even need tools it's a plastic hand screw.

depends. First check for fuel and spark. Its rare a honda pump go out but it does happen. It has happened to me a couple times. Ive owned 14 hondas so this should be accurate. The ignition control module is located in the distributor, its a small square black piece that has four wires pluged onto it. Have that checked and also the coil. We'll go from there for now

The vehicle grade is denoted in the 6th digit, in your case "4" indicates an RS model.