Sound like a loose wire?

Redog · 08-08-2009, 09:02 AM

OK My oil gauge has been going nuts for a while. I figured that it was just a loose wire but I tighened then today (ones on the back of the gauge) and the ground inside the fuse box and it's still doing it.

I'm thinking that the wire inside the dash for ign is loose. I only used one of those clips and it's connected into the orginal bus for the radio (remember I put in the Navi radio) and it's tucked behind the "box" for the radio and the bus for the radio in in there too.

It's a tight fit, very tight.

The gauge will jump all over the place and then stop jummping and give what looks like a correct reading. At WOT it will go to almost 50 and then right before the shift point start jumping all around again.

I'm going to tear into it this afternoon.

Also there is a relay in my dash to turn the radio on and off with the ign. If I didn't put this in, the radio would never fully turn off because the data wire does not send that kind of signal to the radio. I bought an iPod connceter to hook into the radio. I did all the wireing correctly (had to put the wires back into the new conncetor plug) and wired the postive wire and the ground to the respective places on the relay. When I plug in the "box" for the iPod, the radio turns totally off. Nothing at all, and the iPod connector doesn't work. I'm thinking that this is because it's hooked into the relay. I was going to try going into the ign on the back of the radio and see if that works

What does everybody think?

wrestlingandrunning · 08-08-2009, 06:56 PM

is your oil pressure gauge electrical or mechanical?

Redog · 08-08-2009, 11:32 PM

electrical

Today I drove an hour each way and the gague was better but still bounces.

Crusing at 70 MPH oil PSI was shaky at 26 PSI, earlier it was soild at 38 PSI at the same speed. Floored it to get a jump on hte RPM's shot to 38. Get off the highway and on a slower highway, going 60, PSI was higher

Could the sender wire be the problem? It is right next to the the headers

wrestlingandrunning · 08-09-2009, 01:26 AM

that or it may be the gauge itself and it's having electrical problems. but my oil pressure runs a lot higher than that it's usually just below 40psi idling and goes up to maybe 50psi if i acclerate hard

wrestlingandrunning · 10-20-2009, 11:10 PM

Did you get your problem fixed, my fuel pressure and oil pressure gauge is going crazy from 40psi-100psi over and over again. I checked the wires there fine, there fairly new gauges. It doesn't always happen but I was told check the ground by my local audio shop, I probably should redo the fuel pressure one, but the oil pressure is fine. Could it be because I ran the oil pressure return wire along with a 4 gauge power wire and tucked it in the wire loom?

CactusWill · 10-20-2009, 11:11 PM

I take it that its an aftermarket unit?

wrestlingandrunning · 10-20-2009, 11:17 PM

Oh sorry I forgot to post back in the day when I was preparing to build my alero I got three gauges to monitor things, in my a-pillar. They are prosport gauges blue/white series, there electrical with sending units, voltage, fuel pressure, and oil pressure.

Redog · 10-21-2009, 01:05 AM

No but I think it's a ground issue with the sender

zzyzzx · 10-21-2009, 09:04 AM

Exactly what type of clip did you use to get the power feed from. If it's what I'm thinking of, I really don't trust them. And yes I used to be an electronics technician.

cherrington17 · 10-21-2009, 09:16 AM

how could it be a ground issue... the metal exterior of the sender, connects directly to the engine????? the only other better ground on the entire car, is on the (-) ITSELF!

gotta be a bad connection, or a bad sending unit.

wrestlingandrunning · 10-21-2009, 11:56 AM

You have to ground the sender to something, and I'll have to go check what i used for power something in the fusebox I'm sick in bed but I'll try to check later.

cherrington17 · 10-21-2009, 12:00 PM

Quote:

Originally Posted by wrestlingandrunning

You have to ground the sender to something, and I'll have to go check what i used for power something in the fusebox I'm sick in bed but I'll try to check later.

mine didn't ground to anything. it IS a ground. my whole sending unit has one wire out the back... thats all. works beautifully.

wrestlingandrunning · 10-21-2009, 12:18 PM

Well what brand of gauges did you go with, because from the time I ordered I was very unhappy with them telling me it was in stock to paying for it and it was back ordered. Though for my 300zx I think I'm going to go with AEM. Could the 4ga wire I got running back to my amps be causing electrical interference?

zzyzzx · 10-21-2009, 12:29 PM

I actually did add an oil pressure gauge to a 1975 Chevy I had. The gauge did bounce all over the place, just as you described. I ended up adding a huge capacitor across the terminals of the gauge itself, that helped, but didn't cure the problem.

wrestlingandrunning · 10-21-2009, 12:34 PM

It's weird though it doesn't do it all the time and my fuel pressure reading is off because on www.grandamgt.com they said highest it would be is 55psi so I'm going to try to reground it somewhere else but my oil pressure is grounded at one of the same spots the battery is. So I'll probably e-mail them and try to return it

cherrington17 · 10-21-2009, 12:48 PM

I have glowshift gauges.

wrestlingandrunning · 10-21-2009, 12:53 PM

Quote:

Originally Posted by cherrington17

I have glowshift gauges.

Oh ok I haven't heard good things about them which is why I didn't go with them. Though they did offer me a sponsership and 3 free gauges. So I'll try to reground fuel pressure, and put the oil pressure return wire in a seperate wire loom and if that doesn't work I'll send them back.

Redog · 10-21-2009, 04:29 PM

Mine is Faze, and I'm thinking there is too much teflon tape on the treads.

I did buy an extra sending unit too, just in case