coolant temp reads -

[geno414]

hi every one i put new 1650cc injectors in over the night and when i went to do a log on my dsm link my ecu coolant temp sensor reads -16 degrees and i have no idea why so i unplugged it and then it would read -74 degrees and i thought i had a bad temp sensor so i bought a new one. Well i plugged it in before i got it in my cr and it reads nice but when i installed it in my car it would read once again at -16 degrees so what could be the problem of this i'm clueless ! can any one help me out please thanks.

 

[pauleyman]

If the sensor isn't bad then the harness or connector is bad or there is a ground problem somewhere.

 

[snowborder714]

Any other readings odd, like low/negative intake temps, higher than 1V front o2 readings, high baro readings, etc.? When I see -74° coolant temps, that might mean a blown sensor ground.

 

[geno414]

Any other readings odd, like low/negative intake temps, higher than 1V front o2 readings, high baro readings, etc.? When I see -74° coolant temps, that might mean a blown sensor ground.

I thought it was a blown ground in my ecu but when I looked up a picture of it I couldn't find my ground on it it was weird but it works fine when the sensor is not in the car but once I thread it into the hole it will go right to -16 but if I take off the plug all together it will jump to -74 so I must be getting something

Would a bad intake manifold sensor be causing this problem because I looked into my ecu and there does not seem to be any burn marks or anything can some one help me please I have been doing lots of research to result in no answer .

 

[geno414]

hi every one i put new 1650cc injectors in over the night and when i went to do a log on my dsm link my ecu coolant temp sensor reads -16 degrees and i have no idea why so i unplugged it and then it would read -74 degrees and i thought i had a bad temp sensor so i bought a new one. Well i plugged it in before i got it in my cr and it reads nice but when i installed it in my car it would read once again at -16 degrees so what could be the problem of this i'm clueless .

I thought it was a blown ground in my ecu but when I looked up a picture of it I couldn't find my ground on it it was weird but it works fine when the sensor is not in the car but once I thread it into the hole it will go right to -16 but if I take off the plug all together it will jump to -74 so I must be getting something

Would a bad intake manifold sensor be causing this problem because I looked into my ecu and there does not seem to be any burn marks or anything can some one help me please I have been doing lots of research to result in no answer .

 

[pauleyman]

Why don't you start with what you changed. What all did you unplug, move etc in the process of the install. I'm assuming everything worked correctly before the install. If that is the case I would think you've not hooked something back together correctly, missed a connector or broken a wire or connector during the process.

 

[snowborder714]

Do not create a new thread next time. I've merged the new one to the original one.

The -74 reading is normal for an ECU to display when it doesn't see a sensor. If you plug in the sensor out of the thermostat housing and put it in a cup of warm/hot water, does the ECU see the increase in temp and display that?

Not sure how you couldn't find the sensor ground on the ECU as it shows a picture in the link I posted above. If you're looking at the ECU with the plug area at 9 o'clock (like shown in the picture), it's in the bottom left corner. It will just look like a white strip on the circuit board. If you don't know what you're looking for, post a picture of the ECU.

 

[geno414]

Do not create a new thread next time. I've merged the new one to the original one.

The -74 reading is normal for an ECU to display when it doesn't see a sensor. If you plug in the sensor out of the thermostat housing and put it in a cup of warm/hot water, does the ECU see the increase in temp and display that?

Not sure how you couldn't find the sensor ground on the ECU as it shows a picture in the link I posted above. If you're looking at the ECU with the plug area at 9 o'clock (like shown in the picture), it's in the bottom left corner. It will just look like a white strip on the circuit board. If you don't know what you're looking for, post a picture of the ECU.

it does change when i put it in worm water but when i plug it in the car it will slowly go down degrees i will take my ecu out again and take a picture of it because i look were you are talking about but i still do not see anything wrong with my ecu.

the website will not let me up load my picture of my ecu ut my white wire strip thing is still there .

Why don't you start with what you changed. What all did you unplug, move etc in the process of the install. I'm assuming everything worked correctly before the install. If that is the case I would think you've not hooked something back together correctly, missed a connector or broken a wire or connector during the process.

the only thing i unplugged was my injector wires and put new injectors in that's it and this happened

 

[geno414]

ok for any one out there who can help me not Manny of you are responding and your probably busy but today i got it to start on my dsm link it was reading -21 on the temp but after the car wormed up it started too go up to normal temp but my issue is it will not run at all it has no power it wont even idle with out my foot on it a little my w/b gauge says real lean vac goes up and down everything is weird could that because of my big 1650cc ? i put in or what because i put in the ecu that i have 1650cc but could something else be the problem ?

 

[snowborder714]

I'm assuming your sensor is in the lower portion of the thermostat housing that always sees coolant (and not the upper portion that only sees it after the thermostat opens).

Try omhing out the wires back to the ECU just to make sure they're not broken along the way. I'd also see what voltage that plug is seeing with the car on (doesn't have to be running).

 

[geno414]

I'm assuming your sensor is in the lower portion of the thermostat housing that always sees coolant (and not the upper portion that only sees it after the thermostat opens).

Try omhing out the wires back to the ECU just to make sure they're not broken along the way. I'd also see what voltage that plug is seeing with the car on (doesn't have to be running).

yes it is in the lower part of it. but i also got it started today i will go buy a omh tester but on dsmlink it said that i had on "RAW" 4.79 volts for coolant but that could be wrong i will do a test .

 

[geno414]

I looked at my wires and they seem to be good but as it gets colder out side my temp also gets colder has any one ever had this problem before ? this is my dd and i just having problem after problem with it .

 

[geno414]

some one want to help ? i check this post every day all i see is the number of views going up and the only one left still helping me is snowboarder 714.

 

[geno414]

Can some one shed some light on this its my only car I have.

 

[hotrodssnova]

Did you check the wires back to ecu? If I remember correctly, that whole side runs up by the injector wire loom. I would say you have a broken wire, OR, you have a bad connector on the sensor itself. By putting it in a cup of water, the wires are at a different angle, and that could complete the circuit. Check your plug at the sensor. It needs to be clean, tight, and no cracked wiring.

 

[Wildside22]

My thought is that when you did your injector swap you cracked the wires in that harness.

Have you ohmed out the wire on pin 83?