A while back I posted about POOR fuel economy after doing some towing. I did SeaFoam and reset the ECU (overnight). Still no luck. Car was still sluggish and sucked gas. Shortly after posting it started snowing and being a "real" winter so I kind of forgot about it. Well some good news, I think. Last week I got a check engine light. Had the code read and it is a bad engine coolant sensor. Since I had done the hard ECU reset (at the time of the post) this was the only code and it was there 3 times.

 

The question: will a bad coolant sensor make fuel mileage suffer? REALLY suffer? And any helpful hints on changing the sensor. I can't even find it let alone figure out how to replace it! It is on the right side under the intake runners. Should I just use a torch? :-) Or is there a better way?

 

Thanks in advance,

Greg

The question: will a bad coolant sensor make fuel mileage suffer? REALLY suffer? And any helpful hints on changing the sensor. I can't even find it let alone figure out how to replace it! It is on the right side under the intake runners. Should I just use a torch? :-) Or is there a better way?

 

Thanks in advance,

Greg

 

yes it will. the car cant tell that its warmed up so it stays in an open loop program. This means the car is running according to programmed values, and not according to real world conditions. It can make your gas milage take a dump.

 

yes the better way is called a wrench :-p

 

nipper

yes it will. the car cant tell that its warmed up so it stays in an open loop program.

Thanks nipper, this makes sense. I had stopped at a rest area then went to start the car 4 to 5 minutes later and the bugger would not start. It turned over and over and over then finally started to sputter. This happened each time at 3 different stops. I thought I was going to have to wait for the car to cool all the way down.

 

It hasn't happened since but the light went out too.

 

Is it easiest to remove the PCV hoses and get the sensor from the rear? This will be tomorrow project. I picked the sensor up yesterday.

First of all, what is your year/model/mileage?

 

To answer your questions . . . yes! Extremely sluggish running and undoubtedly miserable gas mileage.

 

A few years ago mine ('95 Legacy L with MT, about 100k miles) stalled in afternoon rush hour at the busiest corner in town and I had to push it across 3 lanes of oncoming traffic into a driveway! Later replaced the ECTS and it's run like a champ ever since. Night-and-day difference.

 

The sensor, IIRC, is at the rear passenger side of the engine, kinda' hidden below the IACV. (Good time to remove the IACV and give it a good cleaning?) Try a search--I know it's been talked about a lot.

 

Sensor cost less than $30 (back then).

 

Go for it! And good luck.

First of all, what is your year/model/mileage?

Sorry I didn't put this info in the follow up post (it was in the original). But to answer your question:

96 OBW, 2.2, 5 speed, 140,000ish miles