wierd temp guage issues???!

[Allforspeed]

lately i have thought that my car has been running a bit hot, so i put a new radiator and 180 degree thermostat with water wetter, but its the same and now i think that it is the guage, cause when i hold the power window buttons down it goes up and when i turn the lights on it goes up more??? what could be causing this?? all my grounds look good, a few months ago i did a 3G 130 amp alternator upgrade but havn't had any problems until this week . i am going to put in autometer guages soon, but would be nice to not HAVE to do that now. been spending a fortune on my car lately............

 

[Allforspeed]

the car is an 1989 mustang GT, by the way

 

[HISSIN50]

the gauge is your best bet. the IVR is supposed to quell irregularities, but it does not do too hot.

if other grounds are good, how is the motor ground(s)? you can try ohming out the sender housing and see how much resistance there is (when i feel anal, i put a ground wire on my electrical senders' housings, in case the teflon tape, etc acts as an insulator and keeps them from reading optimally).

good luck.

 

[Stang8URMPRT]

I had the same problem with mine... It'd go way up to 270... Put in an autometer.... All better now.

 

[Allforspeed]

HISSIN, bro, you answer all my questions, cheers!! wtf is the IVR? i recently went over all the grounds when i did the alternator upgrade, and when i did my clutch last month i redid the grounds on the backs of the heads, i guess thats all the grounds?
i know the stock guage is garbage, but it still worries me, and if i can just make the stock one work for now, would be best till i get my money back on that other screw job i got robbed on

i'll keep that grounding tip in mind for when i do my autometer guage install too.

stang8 did you ever figure out what was wrong with the stock guage? adn when you installed your new guage did you just disconnect the old stock one above the speedo?

 

[HISSIN50]

IVR = Instrument voltage regulator. it basically is an electrical damper to keep the voltage variances in the electrical system from making the gauge needles move up and down too much. i think IVR's were around through the end of 89 (Nick probably knows for sure).

in later years, they ditched them for more built in hysteresis in the gauges.

i might toss 4 bucks at a new sender for the guage - it might look like poop once you get it out. or pop it off and clean it up.

but you really cant polish a turd.

BTW, did you toss a nice fat (i.e. 4 or 2 gauge) ground cable on, as a nice power ground for the new alternator? i would do that if you have not.

good luck bro.

 

[HISSIN50]

oh yeah, i forgot a main point.

i had tossed out the IVR info in case other gauges were acting funny. if not (if it is only the temp gauge), probably disregard the IVR - it would most likely affect several gauges.

good luck.

 

[HISSIN50]

haha, i just saw the edit on the original post. i hear ya bro. even if you run a 10 dollar gauge from the parts store for a few days, you will at least know what is going on.

if you do go with another gauge, what i did:

there is a port on the back of the driver side lower - it is unused (has a brass cap on it). you can remove that and put the stock sender back there. then put the new sender for the new guage in the more accurate front (OEM) port. this way you wont have a dead gauge.

good luck.

 

[Allforspeed]

i guess the only thing to do is just get an autometer than... dang! another excuse to HAVE to buy some upgrades for my car



thanks for the tip as to where to put the sender, it seems like the other guages all work fine, the fuel sender broke last month so the fuel guage doesnt work, but the rest are all fine. so i guess its not the ivr gadget, i KNOW the car isn't overheating, so i guess just drive it nice for awhile till i get the autometer guage.
thanks guys!

 

[Snakeyes]

Hey Allforspeed,

I have the same problem, when I turn the lights on my Temp gauge goes up. I'd appreciate it if you could let me know what fixes your problem (gauge, sender, both, other)?

Thanks,
Jim