Yes i have read all i can on the the other topics about the temp gauge and non of them really solve my issue

Got a new temp sensor and new gauge because the old gauge lost its needle and the sensor wasn't responding all the time....when i get it all hooked up the gauge just slowly wants to creep up. I can turn the key to "on "and get the gauge to creep up all the way to about 220 with out ever starting the engine for more than 24 hours. After running the engine a while it creeps up to where it should be if it was pegging before the fix.

I have check all my wiring and cant find somewhere else where it is grounding.

The gauge is from the Fiero store, and the sensor is a BWD from Adavance Auto

When everything is turned off the gauge sit half way between 100 and parallel with the ground to the left, and when the key is in the on position it sits just to the left of 100 before it starts to creep.

I have done the peg fix where you splice the wires coming from the ignition modual.

I have burped the car too many times too.

Any ideas? really want to get this fixed quick

Thanks

Start by pulling the terminal pins that you swapped on the 'pegging' fix. Just open the dash, pull the terminals out of the connectors and leave them out, then plug things back together and turn the key to on. If you still have a gauge creep, then the problem is the new gauge. If the creep went away, the problem is in the wiring.

i didn't change the terminals in the back of the dash when i did the peg fix.

What terminals should i pull? # and side?

I have pulled the 2 temp wires (for the gauge and light) and put them back in when they are out the gauge just sits there as if the car isn't on

I did get a little movement in the needle when when it was all the way to the right, and flipped on the lights and played with the dimmer...very very little movement...i had that problem before with it moving with the dimmer because there was a bad ground behind the dash but fixed that long time ago

So two things to try. First unplug the cable from the temperature sending unit and leave it off for testing

1 - Put the wires back in the dash the same way they came out and see if the gauge creeps.

2 - If the gauge is still creeping - swap the wires on the dash connectors and then plug them back in. See if the gauge is still creeping.

re: gauge sits dead with the dash wire unplugged - Yep it should do that - so that makes it look like the trouble isn't in the gauge.

re: gauge moves a bit with the lights - Yeah they do that sometimes. Most likely a bad ground but lets get the creep fixed first.

re: what the gauge says with the key off - Fieros use an 'air core movement' for the gauges. That is instead of using an electromagnet against a spring, they use an electromagnet against an electromagnet. The gauge won't become inaccurate as it ages because of the natural tendency of springs to weaken over time. But with the key off, there is no electromagnet, and thus the needle may just sit where it was with the key of or might move and then stop. What the needle does with the key off has no meaning with an air core movement.

[This message has been edited by phonedawgz (edited 10-18-2011).]

wires the same way the same way before the peg fix and it till creeps..

will try swamping the wires on my next day off, believe i tried that and it is still creeping (and i never flipped them to begin with i did the peg fix splicing with the ignition modual ) i did tr flipping them at the sensor and i got nothing, this all again when i have a day off...probably friday

I even took a new wire and ran it outside the car to the engine compartment for the gauge and it was still creeping? with the car off and running both.

I did the same with a wire for the light and since the car isn't overheating it won't come on but if i ground it it will.

I'd be interested in you trying this.
Measure the resistance of the temp sender before you start and log it. Then connect the temp gage lead and let the gage creep up however far it goes. Then quickly measure the resistance of the sender again and see what you get.
My theory is there is current flowing through the sender thermistor which is heating it up which would drop the resistance and cause the gage to creep up. If this is what is happening you should see a lot lower resistance the second time.
If this is the case the question is why. Is there to much current on the sender line, is the sender not in coolant? Don't know for sure...

[This message has been edited by Dodgerunner (edited 10-18-2011).]

I am thinking this might more be the case...don't know how to solve though, because i really didn't change much besides the gauge and the sender, was just fixing the needle the fell off a working gauge and the sender was old and was refreshing the engine area with new sensors and stuff.

Could the block not have a good ground and it is trying to ground through the gauge or something like this? if so what is the easiest way to test and fix? could this also be the whine i am getting in the radio too? I really don't know electrical all that good, and kinda pissed my mechanic off with a daily driver and just messing something up he just fixed, the other day so don't want to go there with this issue,

I have burped the car a couple of times to get air out of the system, and i changed the sensor on level ground, took the thermo out to try to get more are and more flow through too???

It's important for my tests that the temperature sender at the engine be unplugged.

Phone i am kinda confused what you are wanting me to test to begin with actually, if i pull the stuff from behind the dash and the sender nothing happens, and if i flip them nothing happens....

is that what you are wondering?

I need it in simple terms and step by step... not very good with electrical

[This message has been edited by ltlgt88 (edited 10-18-2011).]

With the wires re-attached at the dash, but with the temperature gauge sending unit unplugged, do you still get the creep?

If so then if you swap the wires at the dash, but also still have the temperature gauge sending unit unplugged do you still get the creep?

no i don't get a creep with the wires plugged in the dash and the sending unit unplugged

Radio whine can be attributed to a bad ground...

In aftermarket stereo systems whines show up with bad main grounds (ground on amp) or if the Main power line ("power in" on an amp) is run to closely to the signal lines (wires out of amp to speakers or RCA cables out of the radio going to amp) ...

I never fixed my stock temp gauge (i will one day)... Apparently it did not work right and the previous owner just unplugged it and hid the wires... ugh... (just found them) Before I found them, I got a pillar pod and and aftermarket temp gauge and all was well.

Off topic.... Wow just dawned on me, I added a large engine to rear hinge ground last week. I drove down a street yesterday that had big power lines and I normally got a lot of whine so bad you could hardly hear the radio station. Hardly any at all yesterday...

On your temp gage, you might also verify the sender is correct. You could check the resistance when cold to the current temp and see if it reads close to what it should be for resistance. After market parts you just never know..

Dodge Will have to look at that when the engine is completely cold again, and see what the resistance is..

I did notice when i looked at the resistance when it was running the other day it just seemed to keep going down and down and down even when the car was running normally, don't know what temp but it was like it never seemed to stop... I started the car this morning real quick to try to burp it again to make sure the sensor is in liquid, and as it was warming up the ohm reader was going down.... I will see what it says in about 40 min of cooling off it is going up or down too before i go to work, and then i will check what it is reading when i get home too from work too.

on my ohm reader should i have it set on 2000 or 200???
don't really know how to use a volt/ohm reader, but trying to figure it out. I usually only use it to check grounds and make sure the wire that i am getting is switched or not and things like that.

If the engine is cold you would have to start higher than that since your probably should be between 3400 and 7500 ohms. You can't switch to the 2000 (2K) ohms until it's up around 95° . (if the sender is correct)
If you could check it when completely cold, check the current outside temps (unless it's in a garage) and see if the ohm reading is close to the current air temp.
Yes the resistance change is not linear so it's going to look like it's dropping very fast.

[This message has been edited by Dodgerunner (edited 10-20-2011).]

so if i check the resistance with out even starting the car when it is cold will the ohms read with out moving or will the be moving around?

If it is moving around does that mean something, because of course the temp of the coolant isn't changing if i haven't started the car.

I will have to check it on friday, i left the trunk open all day today and killed the battery, on the charger right now and will check it when i can on friday.

I don't quite understand what the 2k and 200 are all about on the om reader? do i add that to what ever it is showing?

any other suggestions you have would be great, keep them in easy to understand directions as i said i am not the best with electrics and cars.

are there any grounds i should be looking out for? the one behind the radio is good, isn't there one under the dash too somewhere by the steering shaft? i have never been able to find that one? What about on the engine is there any grounds back there that might affect this? does the radio whine have any possibility to go with this?

Has anyone used any of the temp sensors mention or would recommend one of the other? Duralast, BWD, AIRTEX / WELLS, or STANDARD MOTOR PRODUCTS?

The Fiero gauge temperature sender can be read with an ohm meter by putting one lead on an engine ground, and the other lead on the pin away from the side notch of the sender unit.



If the resistance is not where it should be that is the cause of your trouble. This chart is for the temperature gauge sending unit



Depending on your ohm meter, you might have to change the dial to a different range to read the resistance properly. If you aren't able to figure it out post a picture of it and we can help you. Remember that your meter reads all the way from 1 ohm to 1,000,000 ohms You have to look at your meter to figure what range is is measuring at.

Any brand name sensor should be accurate enough to function properly.

//www.fiero.nl/forum/A...100421-2-081542.html

The "range" you select on your meter for ohms is the maximum you can measure on that range. IE if you have a 200 selection the highest resistance you can measure is 200 ohms.( Anything greater then 200 ohms will give various results depending on the meter.) If you have a 2K or 2000 ohm setting then you can meaure up to 2K ohms. It does not hurt the meter to measure higher resistance on a lower range in ohms. You don't want to try to measure resistance (ohms) with ANY power on whatever your measuring. In the case of the temp sender you would have the connector off so there is no issue with that.

If the car has been setting cold and you measure the sender you should see a constant resistance reading. It just should match the resistance value on the table above. If you see a value that is changing it's usually because your moving the probe and not getting a solid connection.
So if the car has been setting and the air temp is 59° when you measure the pin of the sender to the engine ground you would hope to see around 4450 ohms and would need to have the meter range select set to maybe 20K ohms. (or the next setting greater than what value your trying to measure.

[This message has been edited by Dodgerunner (edited 10-20-2011).]

Any suggestions on a fairly good ohm reader?? I think mine has gone bad, every time I test it reads something different or doesn't want to read at all. I think I blew it up when I was running it between the pigtail and the sensor. Also even though the engine hasn't turned on the number on the display still wants to move around just not as fast... was going to swing and get one on my way to or from work today.

My most steady reading I was getting seemed about right but I was also getting readings that were pretty steady that were way off too.

What is the best ground to test th ohm.with? I was using the one on the driver side hinge.

I'd just measure to the base of the sender, the hex part. Also check between the base of the sender to the head itself. You should have 0 ohms (or very close) indicating a good ground between the sender and the head... (what did you use for thread sealer on the sender? Not teflon tape I hope..)
Might also measure between the block and the body of the car just to see how your ground connection is between the engine and the body. Should be 0.
Due to rust on surfaces you can see changing readings unless you scratch around and get a good connection.

Sears actually sells some nice meters. A few even come with a temp probe.
The harbor freight meters are cheap but do work....for a while...

[This message has been edited by Dodgerunner (edited 10-20-2011).]

i just ordered one through amazon should be here tomorrow

i did not put any tap or anything on it was i suppose too? what type of tape should i be putting on it? everything i have read said it needed good connection between the block and the sender, and not to use tape??

I will check all those ground things when i have the new meter...i needed a new meter anyway, the cords had cuts and i had dropped it a couple of times, so it was probably shot anyway.

[This message has been edited by ltlgt88 (edited 10-20-2011).]

Wanted to make sure you did not use tape or teflon paste either.

got the new multi meter today, so much better than my last one

Tested the car while it was cold, it hasn't been started for 3 days, and it was reading about 3300 ohms , and it was about 60-65 outside but the car was in the garage

Started the car with the multi meter on it and let it warm up to operating temp and it was about 330 ohms i have a 180 thermo and chip. I then reved the car to get the temp up higher and the multi meter got to about 215 ohms or so when the Radiator fan kicked in. I have an RD 210/200 degree fan switch. Then i noticed the ohms going back up too and the fan turned off right about 230 ohms.

so matching all those numbers up with the charts above i believe the sensor is correct.

Would i be right to hook everything back up and test the ohms reading at the dash off the gauge wire (not hooked up) and a ground? and see if i get the same type of readings there.
then
If those readings are good test it at the post in the dash where the gauge sits?
and then if those are correct it has to be the gauge itself?

Does that sound about the right plan?

[This message has been edited by ltlgt88 (edited 10-21-2011).]

Sounds like a good plan. Just remember any voltage when testing will change any reading you get.
When you check the wire to the dash plug pulled you might also switch the meter over to low volts and turn the key on and see if you get any voltage on the wire.
Should not be until the plug is connected to the dash.

Was laying in bed last night and started thinking... It would almost have to be the gauge or my pod because i ran a wire from the back of the car to the front avoiding the whole wiring harness and it still did the creeping, still going to retest everything as i put it back together but will be ordering another gauge from FS this week sometime

You can run to radio shack and buy a fixed value resistor and attach it to the lead wire, and ground the other end against the engine.

Then see what you get on the gauge. If the gauge is still creeping, it's not the sender.

Do all your gauges move when you have your turn signals on? You might have a engine ground to frame ground problem.

//www.fiero.nl/forum/Forum2/HTML/043240.html

so did a lot of testing today and lots scratching my head...i can't figure it out so here is what is going on

When the car is off i can get a perfect reading on the multi-meter with the ammount of ohms that would be needed for the temp of the engine or the amount of the resistor i attached for some of the testing (270ohm). I even get the right readings with the ignition turned on without the engine running.

The minute i turn over the engine and start it the ohms drop drastically. I if i ground the multimeter to anything but the actual engine block i get readings 100-150 ohms less than i should when the engine is warm or with a 270 resistor. I tried all the different grounds i could fine (even the one behind the radio)

I did test for voltage in the sender wire behind the dash and when the engine is not running i get like -2.1 mV however when i turn the engine on it is at -21.5-22.5 mV

any ideas?, bad body ground by the battery? crossed wire somewhere?

I am trying to get the ohms reading correct, and then worry about the gauge, i ordered a new one from the FS today shold be here by Thursday

You have a bad ground between where the meter works right, and where it doesn't work correctly.

Most likely an engine to frame ground.

Look at this link

//www.fiero.nl/forum/Forum2/HTML/043240.html

[This message has been edited by phonedawgz (edited 10-25-2011).]

So basicly i need to get a 4g wire and connect it from the EGR part to my battery tray to make a new connection and ground the frame and the body better? or to ground the engine better? done exactly understand what that is going to do.

The other problem i have is that the battery tray area is getting rusted is there an other spot that i could connect too that might be better, or should i just sand the rust away before making a new whole on the tray and connecting with a new screw?

If this doesn't work anyone else got an idea? I might have a chance to work on this on Thursday.... (i only get 1 day a week to put lots of time into the car because we just moved into a new house and i told the wife that i would work on the car one day and the house the other of my days off)

You can ground to the deck lid hinge studs.

I ran a 4 gauge 20" battery cable from the egr bracket to the hinge post/ the same one that had the ground strap, i sanded some of the rust away and re grounded the small cable coming off of the battery to the area below the battery.

Was unable to start the car due to another dead battery today and also in the process of playing with the egr bracket i lost 2 of the fittings from my RD SS vacuum tubes to the EGR solenoid.

Will pick up the 2 fittings hopefully today, and will try to start tonight otherwise i wont work on it tell next week sometime

Should i connect any other grounds between the engine and body? or battery and body? before i try to start and see ?

still getting that variation in ohms between with them when the engine is running an engine is off. it might've been reduced a little bit.but at all warm engine it was still off by about 20 degrees in the ohms readings.

could this also have to do with something with the alternator. I re. place that a while back in that is when the wind started in the radio. hard to test of wine in the radio when the dash is torn apart and it is in the garage . I mainly heard it when I was out on the road . and the alternator is only turning when engine is running . or could it be something to do with the ignition being right next to the wires that run out of the sender. because that also only runs when engine running .

I was getting a -12 to -13 mV which the engine running . and 0 when the engine was off .

where would I be picking up that extra current to reduce the resistance.

I didn't have a chance to test ohms to the new ground that I attached between the hinge and the egr solenoid. I will also tested to the negative terminal on the battery and see what my results are .

[This message has been edited by ltlgt88 (edited 10-28-2011).]

So at what spot does it change?

When you have your negative lead on the engine?

On your new ground wire?

On the chassis itself?

On the battery negative terminal?

If I have the engine off with multi reading ohms and have the + on the sensor/wire and the negative on the chassie, engine or negative cable it all reads right with the ohms of the resistor or the temp of the engine.

The minute the engine turns over and starts the ohms drop if I have the negative on anything but the engine itself... I have to test the end of the new wire that I installed.between the.where and the hinge, and did not have time to retest the neg on the bat.


Let me know if all that makes sense

Going to recollect the neg battery cable to the engine too I think.. where is I suppose to be connected to?. Should I get a new one when I do this?. Or is there a better spot to connect it to?

bump?

I have the exact same problem in my 87 GT. It's been like that since I've owned the car. We talked about it on here for a while and I eventually just gave up and unplugged the gauge wire from the sender. The warning light still works, so I will still have an indication if it's heating up.

I'd love to find a solution though. Eventually, this car is getting a V8 and I'll probably just get aftermarket gauges and run a new harness for everything. If we can't find a solution that is.

Before I gave up, I pulled the cluster out, pulled all the gauges out and cleaned every connection, every pin, every ground. I added ground wires from the batter to the body, and from the engine to the body. No difference, gauge still just climbs.

------------------
Adam
1984 Sport Coupe Auto., 130,~~~ miles, bad duke
1985 Sport Coupe 5 Speed, 55,000 original miles
1987 GT Auto., 155,~~~ miles, partial daily driver
2006 Jeep Wrangler Rubicon, 5" lift, 33" tires, partial daily driver
1989 Yamaha V Max (oh yeah, it's fun!)
1975 Cadillac Coupe DeVille, 25,000 original miles
1936 Dodge Two-door Touring Sedan

Can't remember if this was asked. Do you have the stock radio installed or was an after market radio installed?
Have seen it time and again where someone changed radios and wired into a wrong wire somehow..

the radio worked before with the old temperature gauge . it is a late model g m radio .

I did some quick multi meter test this morning . between the engine in the body I am gettin a10 to 15 millivolts difference . I believe these small millivolts are running up the sensor wire and into the dash .

I only get this millivolt difference when I am running the engine . I even get a millivolt difference between the negative battery terminal and where the negative cable connects to the engine . I have a new negative battery cable on the way a new temperature gauge on the way and if I get real ambitious a new positive battery cable on the way . I am not positive about doing the positive battery cable because I am unsure of the routing and where it connects to behind the engine .

also still wondering if there would be something with the alternator making the millivolts between the body in the engine .

as I have stated in previous post this is my first time doing electrical repairs on a vehicle . I am quite unsure of how all the different components interact with each other and what would interfere with each other

can somebody please pass between there engine and body and battery and inside ground , and see if they get a millivolts reading

y