Temperature display says car is hot and brake pedal is real hard barely stops car

LEOKIND

MEMBER
1998 TOYOTA COROLLA
1.8L
4 CYL
2WD
AUTOMATIC
100,000 MILES

Engine temperature display passes "H" within five minutes. Fan was working now only when A/C is on car is running in park. Radiator cap is off a little coolant will overflow out top when turning off car little more coolant will come out. I changed thermostat and sensor next to thermostat. Does thermostat need to be certain position like at nine or three o'clock? I am going to change radiator the coolant is pretty hot but radiator fins are cool to the touch. The check engine light is on. Also, brake pedal is super hard it hardly stops car. Please help need car to get around!

1 Reply

STEVE W.

MECHANIC
13,573 POSTS

Have the car scanned for the code(s) that are turning on the CEL.

Hard brake pedal sounds like a bad brake booster or the booster vacuum line is cracked/broken. That should be easy to find, just follow the hose to the intake.
That would let air in without the computer knowing it and that could lead to a very lean running engine. Lean = heat. Heat on a small four cylinder is not a good thing.

Overheating in under five minutes suggests you may have a head gasket failure from it getting hot. It also sounds like the fan control is not operating which leads to more overheating.

I would start with a pressure test of the cooling system, then flush it, then as you feel the radiator is defective, change it out. If the system holds pressure test the fan control sensor and relay for proper operation. One or the other is faulty if the fan is not activating.