Question on Electrical gauges...

[K_Arts]

Ok guys. . I have a wierd scenario for you that I can't figure out.

I currently have Autometer Ultralights gauges and I am going on my 3rd EGT gauge. For some reason every gauge that I have installed goes Haywire on me. At any given time, the needle on the gauge will just start jumping all over the place. I am wondering if the autometer EGT modules are just cheap.

The reason I am wondering this is because of this. I have the hot side of my transmission gauge and my EGT module joined together and spliced into the ignition wire. But the strange thing is that while I am at an idle, if I tap my power window switch then that makes the needle on my EGT gauge jump around, even though the transmission gauge is fine. Have you guys seen anything like this? Why does my truck kill every Autometer Ultralight EGT gauge that has been installed? Any suggestions?

Thanks

Kev

 

[Cooker]

Kev,
It sound like the gauges have too much draw on your ignigition circuit. You may want to consider wiring in a relay and powering them off of that.

Sorry I can't help you woth your gauge question though.

Ryan

 

[dresslered]

I'm not familiar with the ignition circuit but I have alway recommended tapping into the "switched" Cigar lighter circuit. This is a 20-amp circuit and a separate, smaller fuse may be added inline for the gauges. The one thing that you should remember though, is that the pyro gauge uses an internal amplifier and could possibly be very prone to noise. Use a separate power line or a large gauge wire. It really sounds like your ingition circuit is inducing noise and/or dropouts on your supply. Most of the other gauges are much less sensitive.

Additionally, just as important as the supply and is often overlooked, is proper grounding of the instruments.

------------------
David Dressler
2001 Driftwood 3500 Quad Cab 4x4, 155 inch WB, HO Cummins (ETH), 6-Speed (DEE), SLT+, 3. 54 LSD, Camper Special, Trailer Tow, Heated Leather, Sliding Window, Jacob's E-Brake, Rhino Liner, VDO Vision (pyro, boost, engine + diff. temp. ), Weather Guard Diamond Plate Saddle Box, Tork Lift camper tie-downs, Mag-Hytec, Mopar Tow Hooks, AND functional Halo light!
Bigfoot 3000 10. 11 Slide-in Camper. "Do it in a Dually"


[This message has been edited by dresslered (edited 04-09-2001). ]

 

[K_Arts]

Thanks for the offer JNutter... but I have actually been dealing with Autometer directly... and this will be the 2nd new gauge and probe that they have sent me. Even though the autometer ultralight gauges suck!!! Autometer sure has been great to me.

I'll keep you guys posted.

Kev

[This message has been edited by K_Arts (edited 04-09-2001). ]

 

[EMDDIESEL]

As mentioned by somebody else, try hooking it up to its own 12v Source. I have mine hooked up to the ciggarte lighter fuse. Dont use that source for any other accessory. Same with the ground. Use a self tapping screw and ground the box by itself. I would be 99% sure it is an electrical interference. If changing your power source does not solve it, mount the box somwhere else. Dont mount the box near any part of the wire harness of the truck. Where is the Gauge mounted? that could be an issue too. I have mine in the A pillar and i have several freinds who have thier EGT's mounted there with no problems. From expierience, any time you have an electric gauge giving erratic readings it is always either a defective gauge (Or control box) or an electrical interference. If you have changed the gauge itself out twice, try changing the box, if its not that, it could be the Thermocouple, but i have never heard of that. They either work or they give no reading, i have never seen a Thermocople make a gauge needle jump around.

 

[K_Arts]

EMDDiesel - I have my gauge mounted in a dash pod located in the middle of the dash board. Though I do have the control module located right under the steering column on that crossmember. I wonder if all of the wiring right under the steering wheel could be causing the interference?

Once Autometer sends me a new gauge and module... then I'll try relocating that box and seeing if that helps out. As far as the ground goes, I have mine mounted on the firewall right there on one of the screws at which the steering exits the cab. Make sense?

 

[EMDDIESEL]

I have my box mounted under the steering column too. Try this, when the new gauge comes, hook it up to the box but dont mount it yet, just let it sit on the seat, then go for a drive, see if the gauge still fluctuates. If it does and you tried moving the positive and negative power sources, and it is still fluctuating, aside from double checking all your connections (Especially the Thermocouple connections at the box. Call Autometer back and tell them you have offically tried EVERYTHING and the thing still does not work. Let their engineers devise something. I am not an electrical engineer so i cant tell you any more then i already have. What would be really good is if you know somebody who has the same EGT gauge in his Ram (Does not matter what style of gauge IE: Sport comp, Ultra Lite, etc, they are all the same inside) and hook up YOUR gauge to his box in his truck and see if it works, if it does, you know it is not the gauge and it is something in your truck. Lastly, do you have a stereo amplifier in your truck for an aftermarket radio? i had one instance where a friends amp had a short and caused his check engine light to come on and his headlights to dim erratically among other bizzare electric problems (He thought his car was possessed). If you do have an amp, pull the fuse on it while you make these tests. If still no luck, let me know, i will call my pocket protector wearing electrical genius dork friend of mine. He might have some ideas, Good luck

 

[K_Arts]

Well, I also tried wiring the gauge to directly to the battery with an inline fuse holder that has a 3 amp fuse, and a toggle switch to turn it on and off... but no such luck.

Maybe I will try to wire in a relay and see if that helps.

Kev

 

[Guest00]

If going directly to the battery still does not correct the problem then a relay won't change any thing. I have a Autometer pyro I will sell you. When I opend the box and found an interface module I ordered a direct read pyro of another brand.

------------------
2K, 2500, Quad, SB, 4x4, 3:54LSD, A/T w/ DTT VB, TC, TC SAVER and AUX COOLER , REESE 15k 5th slider, EASLEY BULL BAR, MAAP NERFS, BFG-TA's, 9000's,TORQUS MAXIMUS 505 lbft ECM, stealth DD2's, Bully Dog Boost & elbow, ISSPRO pyro, boost & transmission, Turbo Lifesaver, JARDINE 4", PAC BRAKE, MAG HYTECH TP& DC, AFE filter, GEAR VENDORS OD, TAYLOR WING onboard.
pullees:
#1 y2k ARTIC FOX 5th
#2 22' car hauler w/ 76 Pinto 392cid or 68 Cyclone GT Cobra Jet FB
NRA-LIFE, VFW-LIFE, SoCSA-LIFE, SASS

 

[K_Arts]

Thanks for the help... as a matter of fact I do have an aftermarket amp in there to power my speakers... though everytime my gauge has gone wacky... the stereo was turned off. Once I receive the new gauge... I'll try the tests that you mention and see what happens.

Thanks

kev