Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum - View Single Post - Thermostat housing removed & replaced (P0128)
View Single Post
Old 02-04-2013, 12:04 PM   #1
Focus Enthusiast
Join Date: Nov 2011
Fan#: 91996
Location: Surprise, AZ
What I Drive: 2014 White SE 5spd

Posts: 194
Points 1,471, Level 21
Points: 1,471, Level: 21 Points: 1,471, Level: 21 Points: 1,471, Level: 21
Level Up 72% Completed
Level up: 72% Level up: 72% Level up: 72%
Forum Activity 0%
Activity: 0% Activity: 0% Activity: 0%
FF Reputation: 3 mrdeath2000 Good Standing Member
Buy-Sell-Trade Rating: (1)
Thermostat housing removed & replaced (P0128)

Got a p0128 a week or two ago when driving home about 1am just after it rained and was running my defroster. I assume that I had a thermostat issue back a ways and the only reason the code came up was that it was cold, rainy and the fans were always on with the defroster running.

I deleted the code when I got home and ran it in test mode for 3 days after reading this thread:
Where's the coolant temp sensor on a duratec?

The code never came back.

it stayed between 67C-77C. Never below 67C except when warming up, stop and go traffic it would creep up to about 85C. Never saw it drop to 0C so I didnt think it was the sensor.

Checked out my thermostat and I lucked out it was the cheaper one 26.99 at autozone. Also picked up new intake gaskets, since I thought I would need to replace it.

HOWEVER!!! I was able to replace my thermostat/housing without removing anything. The hose clamps were a tad of a PITA, but I just need to get some long nose pliers. Lost about 1 gallon of coolant.

The old thermostat was closed when I removed it, so I'm not sure what exactly the problem was, maybe a spring issue? spring couldnt hold the coolant back?

After all said and done, tested it today, (the therm had NO temp markings, autozone site says 180*) and it kept going up until about 96*C and just kind of leveled off there. it only fluctuated between 96-102*C. 75mph on the hwy it stayed at 98-99*C. Seems right, since 100C is 212F.

My guess is that with the Sensor between cylinder #2 and #3 that it will be different than those who have the sensor in the housing itself where it may be closer to the actual opening temp?

2014 Focus SE Manual -
2006 Focus ZX4 SE Auto -commuter 110k /traded
mrdeath2000 is offline  
    Reply With Quote