Hey first post on here since i bought my P5. It is a 2002 with 145k miles. The a-hole I bought it from must have reset the ECU before I came to check it out because the day after I get it home it throws a CEL. I took it to Jiffy Lube and the hooked it up to a scanner. He didn't give me specific codes but he said that it is either a thermostat or a ect valve? The car runs/idles/drives great. The temp gauge gets to about 50% or a little less. Has anyone else had similar issues. I would think if the Tstat was bad The car would be overheating but it has been fine. Also pics of where the thermostat is would help I'm Going to try and replace it myself and see if that is the problem. Thanks ahead for any input
Theremostat or ECT valve codes?
- Thread starter GraySurf
- Start date
hornsfan10609
Certified Mazda Tech
- :
- 2003.5 Mazdaspeed Protege x2
Thermostat housing is on the front of the block under the exhaust manifold. The lower radiator hose hooks right into the thermostat housing. Two 12mm bolts hold it on and replace the thermostat seal for the hell of it, some brands include it with the Tstat. Super easy to do, although CTS is cheap and even easier to do, dont even have to drain the coolant. Its right on the coolant block on the drivers side of the head where the upper radiator hose connects. If the temp gauge isnt reading hot they are probably both fine. Read the code again and post it up, autozone will scan it for free.
does anyone have a picture of the thermostat housing? will an autozone thermostat be good enough or is there a better one? is there a gasket that needs to be replaced as well? sorry for all the noob questions. Searching has not come up with much info or help
Tiajaunatoad
Member
- :
- 2012 MS3
Just install a new thermostat and gasket. Make sure the spring side is towards the block on installation.
So after I put a new thermo in the housing is leaking a little coolant from the bottom bolt area. I took it to pepboys and there parts counter said there is two gaskets? And they gave me a gasket that doesn't look right at all. It is kind of a diamond shape with a hole that is maybe half the size of the housing hole. I can post a pic soon. Does anyone have a picture or part number for the gasket? And are there supposed to be two?
Theres only one gasket for the thermostat and that is the black o ring that goes around the thermostat. If they sold you any other gasket its for the thermo housing to the block. To correct the leak, make sure the o riing gasket is properly installed on the thermostat, the two bolts are tight and the clamp for the lower radiator hose is not loose. Also for piece of mind, permatex sells a gasket maker for water pumps/thermostats. You can put a bead of that around the housing mating surface and then bolt it up.
The check engine light was most likely for incorrect coolant flow. The guy who sold it to you probably had an overheat problem that could not be figured out or was too much to fix. So by removing the thermostat, it made the car run at a fairly normal temp by creating more coolant flow to the radiator. So do not be surprised if the car overheats with the new thermostat in place.
- :
- 03.5 YLW MSP
If its a fail safe t-stat it would stick open and in your case no t-stat yeilds the same results. The car never reaches operating temps withing a certain duration of time and trips a CEL and from the looks of your pictures. It appears that he only had straight tap water in the block. Now thats saying its a warm day outside... if its cold the car will never reach operating temps.
The car will still run at normal operating temps even with no t-stat in it providing its a warm day outside. It will just take a lot longer to warm up is all and trip a CEL. Coolant flow has nothing to do with it but the fact that nothing is regulating the temps on warm up.... i guess that could be argued as incorrect flow in a round about way.
- :
- 03.5 YLW MSP
Thanks for everyone's help. I finally got it all sealed up. I hope this fixes that check engine light. I would be pissed if the guy I bought my p5 from sold me his problems. Plus I think my struts on my driver side are going out my car looks like a fat Guy is sitting on the drivers side.