i recently got a obd II actron scanner for my hyundai 2001 accent and checked for codes...and the code P0118 came up which is the Ect Sensor (engine coolant sensor) but then replaced it with a new one and scanned it again.... nothing came up it said no codes found..Pass....but the car didnt start!!! whats wrong what do i do???

First thing I would check is that you make sure everything you touched during the sensor changed was put back correctly. Like if you disconnected the battery that all the cables are re-attached and tight.

yup i tried and check all the wires and everything seems to be fine and the car won
't start what do i do??? starter fluid didn't work

Does the engine crank? If the engine cranks with the starter, I would check the ignition coils first.

ya it cranks i even replaced the coils with a new one and it still wasn't starting....ahhh what do i do??

I just got through going with this no start problem with my '01 accent.

Mine was the Crankshaft Sensor. I replaced it with an after market one from Autozone and it still ran sometimes and other times would not start. Turns out the sensor was a little different in size than the original one and the bolt that held in the original sensor was too short, causing an intermittent connection. The dealer did diagnosis and found out this was the problem, put in a longer bolt to hold the sensor in tight and my problem went away.

It's a long shot, but you could have a bad connection at the coolant temp sensor. I was getting a code for the crank sensor, and after I replaced it, it went away, but the car still would not start.

Also, make sure nothing is unplugged (Although you have probably already done that).

i did notice the new sensor was a little bigger than the old one...
should i take it to autozone and let them diagnose it or what???
help!!!

where is the crank shaft sensor located??
where can i see a diagram?
help!!!

Slow down ..... Geebers ...... Try hooking up the old coolant sensor & see if it goes then

i did and still nothing...
where is the crank position sensor located??

Front wall of the block...... Its all guesswork now tho, as Hyundai's "Fantastic" :innocent:
OBD system seems to be failing you. (Don't take it personally, theys pretty poor all the way round)

They seem to work heavily in tandem with the Camshaft sensor & the two seem to fail with amazing regularity. The two being simple two wire hall effect switches makes the testing of the units pretty ..... Well impossible really.

So I guess you could well be replacing both...... Past experience would suggest that you you get both & replace as a pair, otherwise this job is going to drag on & on & on :(

how much do those two run for??

Google fourgreen & send em ya Vin & they will tell ya pt #'s & prices

i heard the crank sensor doesnt come up on the obd II scanner
why is that??
btw is the etc(engine temp. coolant senor) required to start the car??
thanks...

It came up on mine when it initially failed. I got an error code.

However, I replaced it, and the code went away but the car still wouldn't start!!

I learned that I replaced mine with an aftermarket sensor, and the length was different, therefore the bolt holding in the stock sensor wasn't securing it tightly enough, so the dealer put in a longer bolt and tightened it up, presto, it has worked fine ever since. Make sure those sensors are making contact, and that they're snug and securely held by the bolts.

koo thank you sir!!!