coolant temp sensor

T

thecrash91

Member
:
2003.5 Mazdaspeed Protege
ok so i think the coolant temp sensor is the reason for my cel problem (bank 1 rich) because i have other problems related to coolant temperature. my question is is there a difference between the sensor that sends to the dummy in the dash board and the one that sends a specific temperature to the ecu? the dash shows temp just fine its the ecu one i need, i know they are two seperate parts so im asking if they are basically the same part in two seperate locations. also where could i go about finding it on the car? pics would be superb. thanks in advanced.
 
2 separate parts? its the same part, it reads temp and shows the temp on the cluster

i doubt thats your bank 1 rich problem
 
justanothermp5 said:
i doubt thats your bank 1 rich problem
Click to expand...

x2 when I had the P0172 cel it was the injector o-ring's.They didn't seat right and were sucking in air (vacuum leak). Sprayed with carb cleaner and car would go to shut off.Fixed that problem and no more cel might wanna look into that.
 
Last edited:
thecrash91 said:
i was informed by HondaEat-R that there were 2, one for gauge and one for the ecu. ive done research and found this quite relevant in most cars, in fact theres typically 3, one for rad fans, one for gauge and one for ecu. heres a link i found that older miatas at least have 3
http://forum.miata.net/vb/showthread.php?t=391638
Click to expand...

well im just sayin...ive been working on my car for a while, ive had a faulty coolant temp sensor, and when it was bad, it showed a CEL saying it was bad
even the service manual doesnt show any 2nd sensor, so as far as i know there is only one, but maybe im wrong on this one

edit: straight from the service manual
Possible Causes:

• Misfire
• HO2S (front) deterioration
• HO2S heater (front) malfunction
• PRC solenoid valve malfunction
• Pressure regulator malfunction
• Fuel pump malfunction
• Fuel return hose clogged
• Purge solenoid valve malfunction
• Purge solenoid hoses improper connection
• PCV valve malfunction
 
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The car doesn't actually run rich though. Hence why I think faulty sensor. I have a wideband. Also only get cell when I start the car after the 6 hour cooldown after cel reset and dont let it warm up before driving. As long as the car is 100% warmed up I get no cel.
 
well that sounds like a bad 02 sensor, not a bad coolant temp sens.
if you have a wideband and the AFR's are good, then it has to be the 02
 
o2 was replaced 7 months ago. its deff heating if im having problems only before the car warms up. also my boost afrs suck before the car gets over 175 degrees F, (the coolant) i have seperate coolant temp gauge as well. i also read that the coolant temp sensor can cause the CEL for what i have. since the ecu cant properly know what the engine temp is its hard to calculate the correct afr therefore it throws code. i guess idk. i have NO performance issues whatsoever with the CEL
 
If you think it's the sensor then change it already. I did it a few weeks ago, it's a bronze colored fitting just to the right of the valve cover on the coolant hose.(looking at the front of the car) It unscrews and the new one drops right it, it takes 5 minutes max and costs less than 15 bucks.
 
yeah changed it and i was wrong =[
ive checked for leaks in the injectors by spraying water, also checked for vac leaks the same way although i have a good 20 vacuum. ive checked my pcv valve the only thing was it was not all the way in, it was sticking out verrrry slightly, the MAF was changed to a low mileage one, and no dice, also the o2 sensor (bank 1) was changed by the previous owner about 8-9 months ago. i have no performance issues at all and what confuses me is when the light comes on changed, it used to be random after resetting the ecu then it changed to when i turned on the car and let it heat up then let it sit and cool down then started and drove it without letting it heat up, but if i let it heat up it would not go on. now its back to random but it does not go on the fist time driving after resetting the ecu. I have driven 200 miles right after resetting ecu non stop and the light didnt come on, but the second i drove without letting it heat up the light popped on, so does that indicate evap system? cuz as far as i know the evap system checks after a 6 hour cool down or something along those lines.
 
SO, if you are still with me with my last post here are my possibilities as posted by justanothermp5

Misfire - no misfires
HO2S (front) deterioration - front o2 was recently changed
HO2S heater (front) malfunction - front o2 was recently changed
PRC solenoid valve malfunction - possible, how do i test? if possible
Pressure regulator malfunction - possible, how do i test? if possible
Fuel pump malfunction - i doubt it since i have no other symptoms
Fuel return hose clogged - possible, how do i test? if possible
Purge solenoid valve malfunction - possible, how do i test? if possible
Purge solenoid hoses improper connection - possible, how do i test? if possible
PCV valve malfunction - doubt it i have the millenia pcv but it was out as described in my last post
 
bumpity? does anyone here have the list of how the checks are done when resetting ecu? i know one of the last ones for evap i believe is the car has to be fully heated up then sit for 6 hours or something like that. anyone?
 
i really dont know what the PRC solenoid valve is, but i do know that the purge solenoid is the sensor that is connected to the charcoal canister in the far left of the engine bay
not sure how to test, but just make sure that the connection is good and that there isnt any cracks in the hoses

and i would really let the car warm up a little before driving, especially with the forged internals
 
ive tried but cant find, can anyone help me find the part for purge solenoid and prc solenoid, ive tried rockauto and onlinemazdaparts but came up dry. thanks, im going to do a little research and use that along with the price of parts to decide which one to knock off my list next, cheers!
 
ok so i think i found the purge solenoid. is this it? i found it on top of the IM closer to the throttle body side. had 2 hoses in it and a Mitsubishi logo, it is exactly identical to the other Mitsubishi solenoid on the passenger side of the car in the back of the engine bay which im pretty sure is the MAP sensor? Let me know, also not sure if this means it bad abut i can blow right through it, also if you take off the Mitsubishi logo in the pic there is another nipple which is what separates it visually from the aforementioned Mitsubishi solenoid Thanks for info.
4kuvrp.jpg

im5npe.jpg
 
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