94 accord ex 2.2L. She's running pretty rich (and fails the sniffer). The ECT gauge only goes up about 1/4 of the range. My guess is the sensor as failed and it's stuck in open loop. I've found two possible coolant sensors. One is on the front of the engine (on the upper radiator hose neck) the other is on the thermostat housing. I've unplugged both sensors but the gauge on the dash doesn't move (yeah, I know that's a crappy test). Is there a 3rd coolant sensor?

Yes, I have replaced the thermostat.

 

the 2 wire sensor under the dist going into the head is the ECT for the computer; at "room" temp it should read around 1k ohms resistance, as the engine warms the resistance drops, If I remember correctly it will be below 100 ohms [maybe 50] at operating temp
to answer your question about the guage sensor, look for a single wire connection in the head under the dist.


Modified by hondadude at 8:53 PM 1/12/2007

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hondadude &raquo;</TD></TR><TR><TD CLASS="quote">the 2 wire sensor under the dist going into the head is the ECT for the computer; at "room" temp it should read around 1k ohms resistance, as the engine warms the resistance drops, If I remember correctly it will be below 100 ohms [maybe 50] at operating temp
to answer your question about the guage sensor, look for a single wire connection in the head under the dist.


Modified by hondadude at 8:53 PM 1/12/2007</TD></TR></TABLE>IIRC, from my understanding the single wire is only the sending unit to the temp guage. It does not share info with the ecu, so it should not affect your emissions. You most likely just need a new o2 sensor and the 2wire sensor under the dizzy. I may be wrong.

 

Thanks, I'll give that a try.