I pulled a code P0128 on my car and have narrowed it down to a bad coolant temp sensor. When I start the car, the fans will come on, with and witout the heater on. I am assuming this is due to a bad sensor.

I tried to replace this sensor over the weekend and didn't manage to do so because the sensor is in a very tight spot. I can't get to it with wrench because there isn't enough room to rotate the wrench. I tried with a deep well socket but the downward angle is too large to get a swivel and rachet in there. Can't remove the aluminum bracket that the dogbone engine mount attaches to either because the sensor is in the way for the last bolt. Lastly, I started to remove the crossover exhaust pipe but said screw it, there must be an easier way. The only other way I can see is cutting off about an inch off of a deep well socket to get in there. Any tips to remove this thing?

so that's why my fan comes on???? wow i threw that code but it went away now i will get that fixed so my fan isnt on when it's not supposed to... haha

I don't have any sorry, but Blackarrow did suggest replacing this to improve my gas mileage so he might know.

By the way, when you do get it replaced let me know if your gas mileage improves any.

a real stubby wrench?

A stubby wrench might work, or something like these, in metric: Gearwrench (I love mine.. ) This is the reason I always recommend replacing the ECT sensor when resealing the LIM, cuz they're a PITA to get at..

See if you can get someone to scan it to read the actual temperature output. Also if it is reading really low or high, the PCM is probably running fuel a bit richer.

I remember doing mine for the top-swap and having to be careful with xXLankyXx's ECT sensor when we replaced his LIM gaskets.

A gear wrench *should* be able to get in there well enough.

But yeah, that sensor is a PITA.

I'll try either cutting a 3/4" wrench in half or cutting down a deepwell socket to get it.

I managed to replace the ECT sensor over the weekend. I had to use a 3/4" racheting box wrench to do it. It had just enough angular movement to loosen the sensor. The upper radiator hose must be detached from the lower intake as well. Make sure you have the new sensor ready to go when you remove the old one because radiator fluid starts to gush out upon removal. I slapped the new one in there real quick.

I then disconnected the battery for 10 minutes to remove the codes. The next time I drove it, I noticed that the temperature was hovering higher than before the sensor replacement. This is what I wanted to see. Well, on the way to work today, the SES light came on again. The only other thing to replace is the thermostat. I'll do that this weekend. If that don't fix this code, I don't know WTF to do next.

Glad to hear you were able to change it; you may need to bleed the air out of the cooling system: Replace Thermostat (See Step 8)

Yeah, I've found that bleeding the air out of the cooling system after you open it for any reason is a must.

If you don't, you'll be adding coolant 8 oz. at a time for the next 4 months. I learned that the hard way after I changed my water pump.

On top of the thermostat housing is a jam nut and a bleeder screw that's actually pretty easy to get at. Just follow the instructions per Blackarrow's link, and you'll be fine.

I replaced this after my swap... It was a MAJOR PITA to do, but I had a small enough wrench and did little 1/8-1/16 turns and very slowly and painfully got it off.

What temp thermostat are you running? If you are running a cooler then OEM stat and a OEM PCM, then you will get codes thrown at you.

I have a stock thermostat.