MR2 transmission issue

I'm having a weird issue with my 2001 Toyota MR2 (gasoline engine, 139199 km). The transmission indicator and check engine lights are both on. The automatic transmission is stuck in emergency mode, it isn't shifting properly, and I'm hearing grinding noises when it does shift. The error memory has a stored error related to the radiator oil pressure. Could a defective cable or plug connection really cause all this?

4 comment(s)

That's a strange combination of symptoms. I had a similar problem with my old BMW 3 series, although it wasn't exactly the same. The transmission would go into limp mode, which I understand is the emergency mode you are talking about, and I would get some rough shifting. It turned out to be a faulty coolant temperature sensor. The car thought it was overheating, so it was messing with the transmission to try and reduce engine load. Have you checked your coolant level or noticed any signs of overheating? A cooling fan malfunction can also cause the car overheating.

Coolant level seems fine, and the temperature gauge is normal. No signs of overheating. Where exactly is the coolant temperature sensor located, and is there a way to test it?

On my BMW, the coolant temperature sensor was located near the thermostat housing, which is where the radiator coolant exits the engine. But on your MR2, it might be in a different spot, you'd have to check the service manual for the exact location. As for testing it, you would need a multimeter to check the resistance. Honestly, with those symptoms and the error code you're getting, it's probably best to take it to a workshop. It could be a simple fix, but it's better to be sure. I ended up paying around 95€ for a faulty cable.

Thanks for the advice! I took it to a local mechanic, and you were right, it was a defective cable causing the radiator oil pressure issue. They replaced the cable and cleared the codes. The transmission is now shifting smoothly again. Total cost was 95€.

Join the discussion now: