fuel guage and oil gauge pegging out

[roger01]

ok ....back to this again ..i managed to get a new voltage limiter..(.buy the way 75 dollars canadian )
after a couple of hours got the old one out and the new one in ....guess what? guages still pegging out ..do you guys think i could have gotten a bad one ....its a 69

[Ghoste]

Very possibly.  Where did you get it, that seems like a lot of money?

[roger01]

i thought it was a lot of money to but its the only place that has them chrysler dealership....i wanted them to test it before i bought it but they said they couldnt....i hate the dealership....

[Just 6T9 CHGR]

Generally speaking from my experiance, its "normal" for the gauges to spike once in a while.   The antiquated transistorized regulator overheats, spiking the gauges.......... then when it cools, usually a few seconds, they go back to normal.

There is a "fix" for this by using a heat sink, diodes & specific resistors to make your own Solid State regulator that will give you a rock solid 5v refrence and not the pulsing 5v like the old style gives you.  Try and do a Google search for the regulator upgrade (it was on the old site in the archives)

I would leave it alone and not worry about it.   

[roger01]

i do remember the intermitant spiking but now mine are spiked and stay spiked i,m going to try a different limiter and if that doesnt work well ....what do i do next ?i,ll keep you posted

[Ghoste]

Next I'd try and make a solid state one.  I'll try and find a link to a "how to" somewhere and post it up here.  There are plans out there.

[charge70]

I think I'd be looking at the wiring,if it was the voltage limiter wouldn't the temp gauge also be spiking.Try disconnecting the sending units and see if the gauges are still pinned,and work from there.

[roger01]

im sure the temp would be spiking too but its not hooked up yet

[Charger1970]

There is a "fix" for this by using a heat sink, diodes & specific resistors to make your own Solid State regulator

I found an article in a magazine from several years back. (Mopar Muscle magazine, NOV '92 page 10)

I followed their instructions and built a solid state regulator. It didn't work worth a flip. I thought I must have done something wrong so I made a second one. It was the same way. It seemed to get hot and die out.

I ended us reinstalling a stock IVR and just ignore to occasional spikes.

[roger01]

ok i got the new limiter ...now is there anything i should be careful about.... im going to unplug the battery and plug it in... now i noticed that there is somekind of cylinder thingy screwed to the back of the dash with one wire comimg out of it that plugs in with one of the legs of the limiter just so i dont screw it up ....does it plug in with the middle vertical leg .....thanks

[Chryco Psycho]

the cylinder is just a capacitor to absorb voltage spikes , & yes it plugs in with the regulator

[roger01]

ok igot the the new limiter istalled ..bad news again... needles still pegging out and staying there what else can i do or check ...could it just be a bad connetion if all the guages are pegging out then its not the tank sending unit ....right ? someones going to have talk me thought what too check here cause im not one to give up but i think this one may just drive me to the loony bin ....there got to be someone out there who had this problem ....what did you do ...thanks for any help ....

[Chryco Psycho]

if all the guages peg it has nothing to do with the senders unless by some coincidence all 3 failed at the same time , are any of the guges shoirted to the frame  of the dash , they all have to be insulated from the dash frame

[Ex President]

Had the same problem with mine, and no one could give me a real answer as to what to do. I bought a new regulator, "special order from Oreilly's" and it didn't work. I tested, and what do you know..... it was bad. So i returned it, and got my money back.

I found the "homemade" regulator article that these guys are speaking of, and built my own. It fixed all my gauges EXCEPT my temp gauge. It still pegs out for some reason that i cannot figure out. I don't know if that helps you or not, but making the homemade one from radioshak worked for me.

[roger01]

if anyone knows how to do this i would appreciate it ...i,ll give it a try

[Ex President]

Email me.... and i'll send you the article. It has all the instructions you'll need.

colbys@geusnet.com

[Plumcrazy]

Try this. With the cluster unplugged, go to the oil pressure sender and then the fuel sender and check the wires with an ohmmeter to see if they are grounded.
If you don't have an ohmmeter just hook up a standard 12v test light to the positive side of the battery. If when you touch the test light to the sender wires it lights then those wires are grounded.  It's unlikely all the wires to the sending units are shorted to ground but it would be nice to know for sure.

[roger01]

thanks for the advice i guess i have take the whole cluster out to do this .......

[roger01]

in the pic below are all the yellow supplied with 5 volts and what are the blue circ wires ......grounds ?..

[Ex President]

Each post you have circled there are the grounds from the individual sending units....  EXCEPT the red wire. The "second post from the right in your picture there", is your 12v feed to the regulator.

[Nacho-RT74]

nop 12Volts... 5 volts from limiter. the limiter gets 12 volts from the 4th post from left to right throught printed circuit, and the send 5 volts output throught also the printed circtuit board ( the yellowed area on pic )

[roger01]

ok i did the test on my limiter...original one didnt flash stayed on
                                          new one same thing ....i took it back and exchanged it
                                         3rd one same thing light stays on all the time only this the guy says this is the last time i can return it ....so i said well this one better work ....
     now what im out75 bucks and have 2 limiters that dont pass the test ......anyone have an extra limiter that works 

[Plumcrazy]

ok i did the test on my limiter...original one didnt flash stayed on
                                                              new one same thing ....i took it back and exchanged it
                                                             3rd one same thing light stays on all the time only this the guy says this is the last time i can return it ....so i said well this one better work ....
       now what im out75 bucks and have 2 limiters that dont pass the test ......anyone have an extra limiter that works  

Where are you buying them?

Try tappping one on a hard surface and retesting it.  Those may have been sitting around for ages

[roger01]

im getting them from the chrysler dealership there the only place that has them ...i,ll give it a try ...ill try anything i know that im not going back there for another one ....
     back to the guages ...its only my fuel guage and oil pressure guage that are pegging out the temp guage seems to be operating properly rising gradually as it heats up ......
   why doesnt it affect the temp guage .?

[Plumcrazy]

im getting them from the chrysler dealership there the only place that has them ...i,ll give it a try ...ill try anything i know that im not going back there for another one ....
       back to the guages ...its only my fuel guage and oil pressure guage that are pegging out the temp guage seems to be operating properly rising gradually as it heats up ......
    why doesnt it affect the temp guage .?

What happens if you disconnect the wires from the oil pressure and fuel level sending units and then turn the key on ?

[roger01]

ill try it tomorrow ...whats supposed to happen ?... needle just stay down to left ?

[Ex President]

LOL... i must know what fixes this for you. It's so weird that your gauges are doing the exact opposite as mine.

All of mine started working right with the new "home made" regulator, but my Temp. still acts stupid.. 

[Plumcrazy]

ill try it tomorrow ...whats supposed to happen ?... needle just stay down to left ?

All the guages shouldn't move.  And you should get a flashing test light if you check the ends of the wires that connect to the guage sending unit

[martinihenry]

I think this'll help you. These are pics of my conversion, and the article I used to help me out. The data sheet for the LM7805 regulators actually recommend using two capacitors, mounted as closely as possible to the regulator, one across the input, and one across the output to prevent noise and hysteresis (noise caused by the control element inside the regulator switching). Hope this works out for you.

Jason

•
http://www.martinihenry.com/temp/instrumentreg/instrumentreg.html
•

[roger01]

thanks for the info everybody appreciate it ....iwent ahead and did the upgrade it  took me a while to round up the 3 lousy oparts though .
apparently radio shacks up here in canada have been bought out by the source ......well its a source of nothing but garbage and very few electrcal components...
  anyways i couldnt bring myself to solder on back of the board so i took the guts out of my old limiter and mounted  everything on its back so i can just plug it in .
   my gages stopped pegging out ....good news ... the bad news is the fuel guage says full now its climbing slowly to full then dropping to just under full its reacting much differently then beforeas it used to just stay pegged .
  i disconnected all the sending units and put a test light on it lit up every time i diconnected the wire from the gas tank and the fuel guage dropped to empty i touched the same wire to ground and the fuel guage read full ...now i dont know but i think my guages are good and the fuel tank sender is shot ... what do you guys think ........

[Ex President]

Sounds like it..... Congrats on getting it fixed....

Any word on my temp. gauge issue...  

[roger01]

i assume you changed the temp sender unit ...it may be that your wire to the guage is shorting out did you test the wire ?

[Ex President]

Oh yea... all of the above. I even ran a "dummy wire around the side of the car just to "double" check. No workee..

The only thing i can think of is that maybe the circuit board is bad on the cluster. Even though, when i hit it with the test light, all shows good.

So if you hear about a board that might be available, holla at me!!