I think I'm reading the blinks wrong,but I'm getting the water temp sensor code.I'm just curious to know if the water temp sensor will cause the RPMs to just up and down after the car warms up.I start the car,let it run for a bit and it idles perfectly fine,then after it warms up the idle goes up down up down.It doesn't have a tach so I couldn't tell you what RPMs,but if I had to guess I would say it jumps from 1 to 2 grand.Last owner said it needed a new o2 sensor which would explain the second code.
I got the car after a front end collision where it busted the radiator and caused it to overheat for a quick second.
The car is a 98 civic coupe dx with a d16y7.Thank you for your time and any help would be highly appriciated.

 

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if you want to try one ill let you borrow one. just hit me up

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by aallbbeerrtttttt &raquo;</TD></TR><TR><TD CLASS="quote">Having a faulty coolant temperature sensor will cause your idle to fluctuate a bit. Get a new part (roughly costing about $50) and change it, the CTS has 2 wires going into it and should be on your thermostat housing. It should come right out with a 24mm deep socket.</TD></TR></TABLE>

ECT (engine coolant temp.) sensor for the ECU is the two wire plug located below the distributor in the cylinder head, I think your mistaking the thermoswitch for the cooling fan that is located in the thermostat housing.