Community Fixes
Verified repair solutions from SupraForums — 433 fixes extracted from MKIII threads
Priming Fuel System After Long Storage - Diagnostic Port Fuel Pump Activation
After a 1989 Supra sat for approximately 14-15 years, the fuel system was completely drained and rebuilt (new fuel pump, filter, strainer, cleaned tank and lines), but the engine would not start becau...
Spongy Brakes for Years - Rear Calipers Installed on Wrong Sides
Persistent spongy, ineffective brakes despite replacing the master cylinder, swapping the ABS unit, cleaning the proportioning valve, and repeated brake bleeding sessions over the course of 8+ years.
No Power to Dash/Gauges/Windows - Failed Alternator Fusible Link
Car would not crank or turn on at all. Turning the key to any position (ACC, ON, START) produced no clicks, sounds, or movement. No power to dashboard gauges, windows, or radio. However, headlights, p...
Oil Pressure Gauge Not Working - Disconnected Sender Wire Repair
Oil pressure gauge not working due to the yellow/black wire having been pulled out of its connector on the oil pressure sending unit near the distributor.
Driveshaft Too Short to Reach Diff - Center Bearing Mounted Upside Down
After reinstalling the original transmission, driveshaft, and center bearing, the driveshaft appeared approximately 3/4 inch too short to connect to the rear differential. The issue persisted even aft...
No Start / No Spark / No Check Engine Light - Hidden Kill Switch
Car suddenly would not start despite having fuel pressure. Owner had been troubleshooting fuel pump relay and ECU signal issues, but the car had been running perfectly just 10 hours prior with no chan...
Intermittent Brake Pressure Loss - Failing Master Cylinder Internal Seals
Brake pedal suddenly sinks halfway to the floor while driving, as if a brake line had blown. Only minimal stopping power remains from the second brake circuit. The issue is intermittent - brakes can f...
Engine Dies at 1900 RPM When Revving Slowly - TPS Adjustment
Engine dies at approximately 1900 RPM when the throttle is opened slowly from idle (~1000 RPM). When revved quickly, the engine climbs through the rev range without issue.
Surging at 1500-2000 RPM After Engine Rebuild - Faulty AFM
After rebuilding the engine (rings and bearings) on a 1991 Supra, the car starts and idles great with no check engine light, but when trying to rev the engine it surges badly above 1500-2000 RPM.
Rear Brake E-Brake Hardware/Spring Kit Replacement - MKIV Cross-Compatibility
Rear brake drum hardware and spring kit for the MKIII Supra (1989) is difficult to source, with most auto parts stores and RockAuto not listing the correct spring kit for the rear drum/e-brake assembl...
Intermittent No Power and No Start - Bad Alternator Fusible Link
MK3 Supra had intermittent total loss of electrical power and would not start. Replacing the ignition fuse temporarily restored power, but the problem returned after shutting the car off. When running...
Jerking and Check Engine Light Under Boost - Dry Rotted Intercooler Hoses Causing Fuel Cut
Stock turbo 1989 7MGTE would jerk/buck and flash the check engine light when the turbo spooled up at around 4 psi. The car drove normally in naturally aspirated conditions but would repeatedly cut out...
No Start / No Fuel to Injectors - Hidden Kill Switch Behind Radio
7MGE would not start. Car had spark and fuel pressure in the rail, injectors tested good with 12V present at the connectors, but fuel was not being delivered to the cylinders. Car would briefly fire o...
Won't Go Into Gears After Transmission Rebuild - Leaking Clutch Master Cylinder Replacement
After a transmission rebuild with an upgraded pressure plate (2800lb Action Clutch), lightweight flywheel, and new stock clutch disc, the car would not go into any gears. The transmission worked fine ...
Front Oil Leak After 7MGTE Rebuild - Missing Cam Seals
After a 7MGTE rebuild (resurfaced head, metal head gasket, ARP head studs, new oil pump), oil was trickling from the front of the engine near the timing covers on startup. Oil was visible behind the c...
Ignition Lock Cylinder Sticking - Worn Key Replacement
Ignition lock cylinder was difficult to turn or would not operate properly
7MGE No-Start After Top-End Rebuild - Distributor Rotor Misalignment
7MGE engine would not start after a top-end rebuild (valves, seals, gaskets replaced, valves lapped, clearances adjusted). Engine had spark and fuel but would not fire. An explosion/backfire occurred ...
Code 13 (Crank/Cam Sensor) Fix - Timing Belt Misalignment on 1JZ JZA70
JZA70R Supra throwing a Code 13 (crank sensor/cam sensor/ECU diagnostic code). The code appeared only when the clutch pedal was released while in neutral, but did not appear while the clutch was held ...
Three Warning Lights at Idle (Battery, Brake, Lamp) - DOA Replacement Alternator
After replacing a failed alternator on a 1990 Supra Turbo, three warning lights (battery, brake, and lamp failure) appeared on the dash. The lights would illuminate at idle and above 2000 RPM, but tur...
Battery and Brake Warning Lights On - DOA Replacement Alternator
Battery and brake warning lights illuminated on the dashboard after installing a new alternator from Autozone. The charging system was only producing approximately 12V at the battery with the engine r...