Where is situated knock sensor in 4R '91, engine 3vz-e?

I'm pretty sure it's under the intake manifold, threaded into the block. You may have two - one in the middle of each cylinder bank.

Thanks a lot!

Is there anyway to repair it? Or does it need to be changed? Maybe the connection isn't good? I've no idea - check engine flashes all the time, but the 4R runs very well.

I don't know of anyway to test the sensor function itself. You should get the codes from your ECM if you haven't aready done so. There is no way to repair it, except to make sure the connector is on tight.

If you are getting a code for knock sensor malfunction, it is possible that the sensor connection is loose. If not, replace it. Your engine is not going to be running at it's most efficient ignition timing without a functioning knock sensor.

See page 32 of the following article for information.
http://www.autoshop101.com/forms/h24.pdf

I've got the code - it's 52 - means knock sensor - thanks for the article, but there is one more question - does that code means olny knock sensor - or is it something worse? The engine is only 300 miles after rebuild, but before the rebuild there wasn't any problem with this sensor - what could be the problem if the connection is alright?

Probably the wire to the sensor is damaged.

Code means the knock sensor signal is not in the expected range. I don't know of any other explanation besides the sensor or the wiring/connector.

See this link:
http://www.asashop.org/autoinc/JULY/techtips.htm

Thanks. The link is great. I'll try to change the connectors. Hope it'll help.

Thanks a lot once more!

You're welcome.

it's done - all I had to do was to change about 15cm of cable that goes from the sensor to the intake manifold.

Brian - I am very gratefull for your help!

Best regards.

No Problem