1981 toyota cressida, 2.8 l seems like it is starving for fuel idles great, after about 2500 rpm it boggs down. exhaust is clear and secondary ignition is good while acting up.Sensor light is out and stays out.

run the fault codes to find the faulty sensor

Mira 847 cc 1993- Engine Code ED 10
Ignition data

• Ignition system type: El-ecu
• Ignition coil make/type: Dia/-
• Supply voltage: 12 + Volts with ballast resistor
• Primary resistance: 1.35-1.65 Ohms
• Secondary resistance: 22000-30000 Ohms
• Distributor make/type: Den/-
• Contact breaker gap/air: 0.2-0.4 mm
• Dwell angle: Deg\par Ignition Timing - unleaded: 5 2/900 Deg eng/rpm (without vacuum)
• Ignition Timing - leaded: Deg eng/rpm (without vacuum)
• Timing mark location: Flywheel
• No 1 plug location: Pulley
• Firing Order: 1-2-3
• Spark plug make: Bosch
• Spark plug type: WR6DC
• Electrode gap: 0.7-0.8 mm

Fuel System

• Fuel type: U/L
• Fuel pump type/pressure: bar
• Engine idle speed: 900+100/-50 rpm
• Fast idle speed: 2000 rpm
• CO level at idle speed: 1.0
• 0.5 Vol %

Engine Data

• Valve clearance - inlet: 0.25 mm (hot)
• Valve clearance - exhaust: 0.30 (hot)
• Compression pressure: 1.2-1.5 bar
• Oil pressure: 2.5-5.6/3000 bar/eng/rpm
• Radiator pressure cap: 0.6-1.05 bar/type
• Drive belt 1 - size: 9.5x925/KDB 925 mm/type
• Drive belt 2 - size: mm/type

Electrical System

• Alternator output: 10/2500 Amps/eng/rpm
• Regulated output: 14.2-14.8 Volts
• Battery: 12/35 V/Ah
• Starter motor make/type: Den/-

Other data

• Clutch operation type: Cable
• Clutch adjustment: 10-30 mm
• Cambelt failure: Damage
• Cambelt Part Number: 13514-87211
• Tyre pressures: 1.8(26)f 1.8(26)r bar (psi)
• it took me 3 seconds to google this then i realized that this is a older engine then yours

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These will help.
Thanks.

replace trottle poss.sensor

check map senser if thats good check your fuel filter

Check Idle control valve.

replace the fuel filter

check fuel presure but it is not a likely culprit likely the throtle position sensor has a bad spot in it
it is likely thet the vechale seams to act up at arround the same rpm or near same rpm every time

either fuel filter or fuel pump...replace filter since its cheaper. 6-12 dollars at autozone

You are really onto it! Either the TPS or the cable from the peddle. Do check the cable first. Frankster016