99 Accord has trouble starting in cold, Check engine light is on with full gas tank
 

Hello,

I have a '99 Accord LX, Four-door, V6 with 260K miles. Recently, the check engine light has started coming on when the gas tank is full and stays on until the tank gets down to about half a tank or a little less and then it turns off. The car also has quite a lot of trouble starting in the cold. It will sputter on and idle REALLY low and often stall. After it warms up, it runs fine.

I replaced the main fuel relay and this improved the problem slightly for a little while. The car idles slightly better, although the starting issue is still there and the check engine light is still on. I then was told that maybe the problem was the gas cap. I replaced the gas cap this morning and it has had no effect that I can discern.

Also, the battery is less than a year old, so I'm assuming that that isn't the problem.

Thoughts?

I am starting to wonder about the fuel line, fuel pump, chokes and things of that nature. Perhaps there is a part that doesn't function when cold for some reason? Perhaps a part doesn't get the heat that it needs to start? Perhaps a bad fuse? I'm pretty stumped and any help would be much appreciated.

You have ignored the best clue to your problem; check engine light. Go to Autozone or other parts store and ask them to pull the code. Write down the code and post it here; Pnnnn is form of code.

Any recent maintenance? How many miles on plugs and wires.

good luck

I'm going to go to AutoZone this afternoon and have them scan it. I was a little reluctant before because I'm super short on money right now, although I now realize it is a free service.

The code is P0118.

It looks to me like the ECT sensor is bad or possibly the wires that connect to it. Any suggestions?

Anybody have a link (or can describe) where this ECT sensor is so I can take a look at it?

99 Accord has trouble starting in cold, Check engine light is on with full gas tank
 

ECT is engine coolant temperature sensor.

It's #15 above the water pump; it has a 2-wire plug.

Not to be confused with the other 2 water-temperature "sensors":
#13 with a 1-wire plug is for the dashboard temperature gauge
#14 is a radiator-fan-switch

Here's a photo.

Thanks, guys! That helps so much!!! It looks like I might need to remove one or two of the tubes that are in the way. Any advice on that?

Can anyone tell me what the two tubes are that block access to the ECT sensor? I'm wondering if I can remove them temporarily to do the replacement.

You can remove any tube w/ clamp at end. Some may be coolant lines and coolant will spill or you can use a small vise grip to pinch the hose to minimize coolant loss.

good luck