Has my gauge gone haywire?

EZT · 11-11-2014, 01:08 AM

We all know how inaccurate the water temp gauge is, but mine started acting really funny as of today. Mind you, air temperature was low 70s and radiator is full of fluid. I happen to notice my gauge passing by the 7th dot, it continues to climb almost to the beginning of the H, maybe the 12-13th dot and then it steadily drops back to 6 then 7. My entire drive to work which is roughly 40 minutes my oil temp stays right at 215, but the water temp dances back and forth the entire way.

Return trip home, air temperature is now 50 degrees. Oil temp stays at 200 degrees. Again, the water temp gauge dances back and forth the whole way home. Any thoughts?

Jordo! · 11-11-2014, 03:29 AM

If not a failing sensor, thermostat sticking maybe?

How many miles?

SouthArk370Z · 11-11-2014, 07:14 AM

If the water temp is changing quickly and/or jumping 2 or more dots at a time, I suspect the sensor or wiring. If the swings are slow and steady, then Jordo! may be on the right track with the thermostat. Or it could be a faulty readout.

Try monitoring water temp directly from the ECM with an ODB/CAN monitor.

EZT · 11-11-2014, 08:38 AM

83,000 miles. The swings are pretty fast, immediately moving several dots. Will try to monitor through scanner.

theDreamer · 11-11-2014, 11:48 AM

Have you checked fluid level?
When I had a leak and my fluid dropped down to very little I would get a swing temp, jumps up and then back down. Inspected the car and found the leak.

1slow370 · 11-11-2014, 12:23 PM

yup you may has some air in the motor not good, your heads might not have coolant in them and that is how head gaskets get blown.

Spooler · 11-11-2014, 01:08 PM

^^^^^This

I would check for an air pocket and if you have one, look for the leak.

1slow370 · 11-11-2014, 01:28 PM

and if you can't find a leak, well, I know where your leak is and it isn't pretty.

EZT · 11-11-2014, 02:23 PM

My fluid levels appear to be fine, right at the max line on the over flow reservoir.

1slow370 · 11-11-2014, 03:08 PM

let the car cool off and pull the cap on the coolant neck.

Read T · 11-11-2014, 05:11 PM

Quote:

Originally Posted by EZT

My fluid levels appear to be fine, right at the max line on the over flow resevoir.

Check the radiator cap, and even then you could have a fluid pocket in the block or by the sensor. I know S14s were notorious for this.

EZT · 11-11-2014, 07:58 PM

Was not at home all day, pulled the radiator cap for a while and no effect still. Beginning to think I may have a problem for sure though. I have the CSF aluminum radiator, but it's had a small leak from the start (got it used). I recently tried some Radiator Stop Leak for aluminum radiators and my fluid level has stayed perfect sense. However, from what you guys have been saying I may have a bigger problem now.

Tadpole · 11-11-2014, 08:42 PM

Nah, sounds like a sensor to me. My fuel gage dots did the same thing. I took it to the dealer and they replaced both sensors and no more dot issues

1slow370 · 11-11-2014, 08:59 PM

Quote:

Originally Posted by EZT

Was not at home all day, pulled the radiator cap for a while and no effect still. Beginning to think I may have a problem for sure though. I have the CSF aluminum radiator, but it's had a small leak from the start (got it used). I recently tried some Radiator Stop Leak for aluminum radiators and my fluid level has stayed perfect sense. However, from what you guys have been saying I may have a bigger problem now.

was the neck full to the lip of coolant when you pulled the cap? Did it come bubbling out when you pulled it.

EZT · 11-11-2014, 09:00 PM

Quote:

Originally Posted by 1slow370

was the neck full to the lip of coolant when you pulled the cap? Did it come bubbling out when you pulled it.

It was still sitting in the same spot I left it, right at the Max line on the reservoir. Nothing came bubbling out.

11-11-2014, 01:08 AM	#1 (permalink)
EZT Track Member Join Date: Mar 2011 Location: Gainesville Posts: 546 Drives: 09 370z Rep Power: 315	Has my gauge gone haywire? We all know how inaccurate the water temp gauge is, but mine started acting really funny as of today. Mind you, air temperature was low 70s and radiator is full of fluid. I happen to notice my gauge passing by the 7th dot, it continues to climb almost to the beginning of the H, maybe the 12-13th dot and then it steadily drops back to 6 then 7. My entire drive to work which is roughly 40 minutes my oil temp stays right at 215, but the water temp dances back and forth the entire way. Return trip home, air temperature is now 50 degrees. Oil temp stays at 200 degrees. Again, the water temp gauge dances back and forth the whole way home. Any thoughts?

11-11-2014, 03:29 AM	#2 (permalink)
Jordo! A True Z Fanatic Join Date: May 2010 Location: nirvana Posts: 6,394 Drives: 2023 NATM Rep Power: 418	If not a failing sensor, thermostat sticking maybe? How many miles? TerribleONE, onzedge, Zoren 370 and 1 others like this. __________________ Enjoy it. Destroy it.

11-11-2014, 07:14 AM	#3 (permalink)
SouthArk370Z Premium Member Join Date: Nov 2010 Location: South Arkansas Posts: 8,435 Drives: 2014 Challenger Rep Power: 324198	If the water temp is changing quickly and/or jumping 2 or more dots at a time, I suspect the sensor or wiring. If the swings are slow and steady, then Jordo! may be on the right track with the thermostat. Or it could be a faulty readout. Try monitoring water temp directly from the ECM with an ODB/CAN monitor. onzedge and DEpointfive0 like this. __________________ Steering Lock Links - Search The370Z Bookmarklet - FSM @ NICOclub Mankind has progressed past the need for war but we haven't evolved that far. - NachoMahma

11-11-2014, 11:48 AM	#5 (permalink)
theDreamer A True Z Fanatic Join Date: Feb 2009 Location: Texas Posts: 30,879 Drives: 370z Rep Power: 4210	Have you checked fluid level? When I had a leak and my fluid dropped down to very little I would get a swing temp, jumps up and then back down. Inspected the car and found the leak. __________________ theDreamer's Z // Fast Intentions // Uprev // GTM // HKS // TEIN theDreamer's Silvia // URAS // GREDDY Houston Zs // Facebook // Twitter // Instagram

11-11-2014, 12:23 PM	#6 (permalink)
1slow370 A True Z Fanatic Join Date: Aug 2009 Location: In the D Posts: 3,732 Drives: v8 74 260z ;) Rep Power: 7251	yup you may has some air in the motor not good, your heads might not have coolant in them and that is how head gaskets get blown. __________________ ANSWER PRICE LIST Answers - - - - - - - - - - - - - - - - $0.75 Answers (requiring thought) - - - - $1.25 Answers (correct) - - - - - - - - - - $12.50

11-11-2014, 08:38 AM	#4 (permalink)
EZT Track Member Join Date: Mar 2011 Location: Gainesville Posts: 546 Drives: 09 370z Rep Power: 315	83,000 miles. The swings are pretty fast, immediately moving several dots. Will try to monitor through scanner.

11-11-2014, 01:08 PM	#7 (permalink)
Spooler A True Z Fanatic Join Date: Jun 2014 Location: Ga Posts: 13,830 Drives: 2013 Nismo 370z Rep Power: 2684392	^^^^^This I would check for an air pocket and if you have one, look for the leak.

11-11-2014, 01:28 PM	#8 (permalink)
1slow370 A True Z Fanatic Join Date: Aug 2009 Location: In the D Posts: 3,732 Drives: v8 74 260z ;) Rep Power: 7251	and if you can't find a leak, well, I know where your leak is and it isn't pretty. __________________ ANSWER PRICE LIST Answers - - - - - - - - - - - - - - - - $0.75 Answers (requiring thought) - - - - $1.25 Answers (correct) - - - - - - - - - - $12.50

11-11-2014, 02:23 PM	#9 (permalink)
EZT Track Member Join Date: Mar 2011 Location: Gainesville Posts: 546 Drives: 09 370z Rep Power: 315	My fluid levels appear to be fine, right at the max line on the over flow reservoir. Last edited by EZT; 11-11-2014 at 09:02 PM.

11-11-2014, 03:08 PM	#10 (permalink)
1slow370 A True Z Fanatic Join Date: Aug 2009 Location: In the D Posts: 3,732 Drives: v8 74 260z ;) Rep Power: 7251	let the car cool off and pull the cap on the coolant neck. __________________ ANSWER PRICE LIST Answers - - - - - - - - - - - - - - - - $0.75 Answers (requiring thought) - - - - $1.25 Answers (correct) - - - - - - - - - - $12.50

11-11-2014, 07:58 PM	#12 (permalink)
EZT Track Member Join Date: Mar 2011 Location: Gainesville Posts: 546 Drives: 09 370z Rep Power: 315	Was not at home all day, pulled the radiator cap for a while and no effect still. Beginning to think I may have a problem for sure though. I have the CSF aluminum radiator, but it's had a small leak from the start (got it used). I recently tried some Radiator Stop Leak for aluminum radiators and my fluid level has stayed perfect sense. However, from what you guys have been saying I may have a bigger problem now.

11-11-2014, 08:42 PM	#13 (permalink)
Tadpole A True Z Fanatic Join Date: Sep 2013 Location: Lockhart, TX Posts: 1,082 Drives: 13 Nissan 370Z A7 Rep Power: 18	Nah, sounds like a sensor to me. My fuel gage dots did the same thing. I took it to the dealer and they replaced both sensors and no more dot issues __________________ Takeda TR3009P Short Ram Intakes, Custom Dual Exhaust, X-Piped with 18" Resonators & TopSpeed Axle Backs. EVO-R Led Third Foglight,

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Gauge pod	wretched_z	Exterior & Interior	3	06-23-2011 06:13 PM
How do you remove Gauge Cover & cover for tri gauge??	Carbon_z	Exterior & Interior	4	11-26-2010 10:07 PM
Short block install gone haywire	Mt Tam I am	Nissan 370Z General Discussions	14	09-29-2010 10:59 PM
What happened to the tire pressure gauge and speedo in the middle gauge cluster?	rbratton	Nissan 370Z General Discussions	33	01-24-2009 11:28 PM