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Driving home from work (4 miles) and Temp gauge bounces a few times back and forth, and then dies. Fine. Get home and electrical connecter still attached, o.k. Tried to check fuse, but no fuse puller. Wiggled w/ fingers, replaced cover. Started car and gauge now works. Hmmmmm????? Have not checked resistance yet or fuse. My long winded question is this: Has anyone experienced symtoms like or near these, and what was the outcome?
mine fluctuates about 1mm when i turn the blinkers on.
Over the two years I've owned the car, it has worked normally. Then left, right, dead..... Then sit for few while I look at things w/ car off, start and it works fine.
::Bulb:: Any suggestions?
My temp gauge stopped working mid-drive home. Checked sending unit connector and fuse. Everything was normal. Started car, and temp gauge now works. Any suggestions or past experiences? ::Hmm::
Get the fuse all the way out and check for corrosion. It is a long shot, but you said that it worked fine after you messed with the fuse. If not there, look for any signs of corrosion or water entry in the wiring harness.
mine fluctuates about 1mm when i turn the blinkers on.
LOL! F U Titus
Did you drive in the rain today? Maybe something got wet and shorted out? :confused:Quote:
Originally Posted by Machismo
This has nothing to do with anything, but Titus' avatar STILL cracks me up...Quote:
Originally Posted by Titus
It did sit in the rain. I am going to keep an eye on it. I just recently roughed in my hood vents, but they are farther forward. No way just sitting would it have an affect at the back of the motor. I remember a splice I did a while back when swapped head, I'll check it and waterproof. Might as well replace fuse and see if gremlin is dead.
Are you SURE it's connected?
There are 3 temperature devices on the Miata.... one is a switch that sits on top of the thermostat and turns the fans one... two is the one with the green or brown plastic connector that sits at the back of the head and connects to the ECU... three is the one that has a single connector on it that runs the gauges. It is on the back of the head too.
Be sure you are checking the right sensor!
You either have a intermittant 3rd sensor, an intermittant wire, or a bad gauge.
RJ
94+ don't have the sensor that sits on the t-stat housing. I would check the small, single wire connector; I had a similar problem with my 94's gauge after an engine install, and this one was the culprit.Quote:
Originally Posted by channelmaniac
I have an extra gauge assembly if you want to try a different gauge.
Yep, single connector at back of enginge is connected. Fuse is fine, but will replace anyway. Gauge worked at start up this morning for about 5 minutes then went away again. No rain this morning, and I dried everything out last night. Will check the resistance this afternoon. Now just need find out if it's the guage or sending unit.
BR, will come by to look at your gauge and b-ball base this Sat.
Just call and let me know you're coming as we have plans this w/e.Quote:
Originally Posted by Machismo
Sure thing
As Channelmaniac mentioned, there's more than one temp sensor. The temp sensor that goes to the actual gauge is located at the back of the motor near the CAS area and coils. Mine appeared to be connected but the plastic lock clip broke so it would not keep a secure connection and eventually rattled off. I had to replace the end of the wire with the female spade clip. Or you could have an actual problem with the wire further down the line...possible nicked while working on the car or came into contact with the exhaust, etc.
Sounds like culprit, I've put a spade on it mine as well as the old one was so brittle a bird fart would have destroyed it.
If I might resurrect one...I recently picked up a 94 with 138K cheap, because the previous owner said it had an overheating problem. Stop and go traffic only brings the needle to 11:00 position. Getting up to highway speed is something else. Then the needle jumps up past H, then back to 12:00, real jerky and fluctuating wildly back and forth. If this were the gas gauge I'd think it was an electrical short.
I took out the thermostat which had no effect. I can see the coolant flowing in the radiator. There is no bubbling, no coolant smell, no boiling over...None of the normal signs I would associate with overheating in cars I've had in the past. I'm wondering if the temp sending unit or sensor might be responsible? Or gauge? Or is it actually overheating?
I'd bet it's a crappy radiator. Is it still the original??
Or do you have air in the system, is it loosing any coolant??
I'd take a look at the connection on to the sending unit...
it's on the back of the motor, driver's side, and a loose connection will make it go haywire. see if you can pull the connector, put a little dielectric grease on it, and put it back on.
I am not aware of anything wrong with my radiator, but I will have to replace it with an OEM unit because of SCCA stock rules. I really have no timetable for buying the new one other than before 2/2008, but if you think you might want to buy mine for cheap, then I can order a new one sooner rather than later and we can have a tech day to install them. Let me know if you are interested.
Sending unit connection is loose. Plus, wire is exposed and frayed at the spade connector. I can rotate the little plug that comes out of the sending unit, but not the sending unit itself, is that normal or should it stay in position?Quote:
Originally Posted by tailchaser
Oh yeah, not losing any coolant that I can determine at this point. I don't think it's the original radiator, looking down inside it looks clean.
Here is a thought, Fix the wire and see what you get. ;)Quote:
Originally Posted by cam76034
If ya still have a problem replace the sensor.
Or you could always do a 3Bean and pull the motor and put the car in a ::box:: for a year. ::Banana::
I take it you now own a '94 Miata??
Purchased for change he found in his sofa... ;)
The connector on the sensor should NOT turn. Replace it.
Aha! I didn't think so.
Thanks Raymond!
It's a very big sofa that I bought at Sofa King!Quote:
Originally Posted by trickyrix
sofa king cheap. ;-)
Only you folks that have lived on the east coast will understand that it's just not a Sofa King sofa if it wasn't delivered by Norfolk & Way Movers...
When your boss tells you that you've got to relocate, remember to say, "Norfolk & Way!"
Wow, what a difference after disconnecting that pesky wire to the temp sending unit! No more distracting bouncing needle action. Shoulda cut that wire 1st thing.
Seriously, I did pull the wire and somebody has definitely been down this road already; the wire had been stripped and rewrapped around the spade connector so it is loose. Not much room to work with but I'll try to solder it back on and see if that changes anything...if not then next step will be a new sending unit.
Don't solder.
If you can unplug enough items and unbolt the wire harness from the mount on that back corner you can pull it out to work on it.
Use a butt-connector (splice) to add a length of wire and another spade connector to it.
Use crimp connectors to do it so you don't have that point of failure where the wire will break in two from the vibration.
And if the connector itself on the sensor moves, replace it. It's bad.
RJ
Yeah, I can rotate the little connector off the sensor 360 degrees. Thanks for the tip on that and the time I was about to waste soldering.Quote:
Originally Posted by channelmaniac
S.P.F.!!!
It's gotta be the gauge!
Replaced the temp sending unit and connections to it. On the way to the highway at 35 -40 mph the gauge sat at 11:00 the whole time. Wind it up on 121 to 70 and things are looking good...for about a mile, then the same fluttery needle going past H, then back to 11:00. Pull over on the side and no signs of overheating, everything seems normal. Take it up to speed and it happens again.
Any suggestions on how to test the temp gauge? Maybe get an extra and wire direct to it?
NO...
It doesn't gotta be nothin'...
You need to hook some long wires up and connect 'em to a voltmeter... Drive down the road and see what happens.
If it still overheats you should see the needle sit still if it's the gauge. if the voltmeter moves to indicate the car is getting hot then the car is getting hot and the gauge is correct.
If that's the case then you have a blockage somewhere. Maybe the radiator...
RJ
So run the hot wire from the voltmeter to the sending unit and ground to ground, right? Could I just tap into that line so to observe the gauge and the voltmeter at the same time?
I thought about blockage, but shouldn't the needle move in a more linear way, instead of bouncing all over the place?
Thanks for the voltmeter tip, I would not have known that.
Well, hmmm...
Hang on a sec... I'm thinking that won't work as the sensor is a path of variable resistance to ground. There has to be a voltage source somewhere and I don't have the miata wiring diagrams on this computer in the shop. What you'll end up reading is a jumping voltage source from somewhere up the wiring from that variable ground point.
Trace it back in the diagrams. You may just have a bad connection on the instrument cluster or a bad wire somewhere else. When the car warms up can you slap the dash and get it to jump all around?
RJ
Okay, I'm trying to read the electrical diagram, and I'm not too good at this. From the temp sensor is a blk/blu wire that leads to the temp gauge. Temp gauge shares a common ground with the tach, fuel gauge and oil gauge. Then there's a blk/yel wire that connects all these gauges to the fuse box.
So...I should be able to tap the blk/blu wire with my voltmeter, right? As the car heats up there would be current through that wire?
Oh yeah, beat the crap out of the dash with no results.