prado 3.4 v6 5vz-fe high idle

[jas72]

Hi Guys

this is my first post on a forum.

Have an issue with high idle on a 1999 prado that myself, mechanic and auto electician and also electronics technicians can not solve

The air flow meter, isc valve, and tps are all within spec.

Have all the correct voltages at ecu.

replaced sensor for coolant and has been tested as working correctly,

ISC and throttle body cleaned, isc tested open and shut on 12v.

The engine has been run on computer with nothing showing up, timing perfect.

Im suspecting the ecu as the cause.

The funny part is that if the coolant sensor is pulled while running, the engine runs perfect and idiling at 750 compared to its normal 1100.

Any ideas would be appreciated.

regards

jas

Edited June 6, 2014 by jas72

[Rod Baker]

try another ecu some one must have one

you could test it with