Hello,

I am currently fixing up a 1988 IROC Z. Most of my gauges don't move. The oil and battery move but I'm pretty sure that they are not accurate. The battery may be right because its at 13 but the oil I'm pretty sure is wrong because it spikes all the way up and my other gauges don't move at all. I don't think its a fuse because I tested them with a test light and the only two that didn't work were the 3 & 5 I forget what they are. I was wandering if someone can give me a link to the wiring diagram or could possibly tell me how to fix this or give me their opinion on it. But a wiring diagram would help the best. If anyone can answer me soon that would be nice because I'm working on it right now and Im about to leave to go buy a thermostat and it would be cool if I knew what I needed to do to make the wires work. Just incase I needed to buy something while I was at the store.


Thank you for any help in advance..

 

Just a little update for anyone reading. I noticed when I rev the engine my oil gauge goes up like the Rpm gauge should. What could this mean? Thank you. I could give any info you need by the way need a pic? I could get you one.

 

Its kind of making me think that the gauges are hooked up wrong how do I look to determine if they are or not. If this is in a post somewhere on here can you please tell me because I looked and cant find anything thank you once again.

 

Oil Pressure should increase when engine revved - higher rpm's = oil pump turning faster = pumping more oil = higher oil pressure.

I'd start with replacing the oil pressure sending unit for the guage.

Most all cars I've ever owned that had a voltage meter usually read about 14 - 15 volts (alternators usually feed slightly more volts than battery holds) - but as long as car always cranks without hesitation, should be fine. Can have battery and alternator both tested for free in the car at most any major chain auto parts store.

 

The car runs great now... When I first got it it was running really rough. Kind of sounded like it was loosing power. I bought new plugs & wires for it it made it a little better. I just got the engine codes and the only one I had was a 15 and thats the temp sensor. So bought that and now it runs great, that made me really happy haha. Im in the middle of taking my dashboard apart but I cant get my hand in to disconnect the cable. Im assuming Im doing something wrong but the haynes manual said to take the dash pad off and I did. But there is still another plastic piece on top of my gauges should I take that off also? The plastic piece the speker was attached to its like the bottom of the dashpad.

Oh also bought a new thermostat and gasket for it and flushed the cooling system then put some new anti-freeze in.

Thanks for the reply..

 

what cable are you trying to disconnect? Speedocable? If so what helps is to lower the steering column by unscrewing it from the bottom of the metal that backs the dash. If you look under the dash you'll see the two size 12 or 13 hex heads holding the steering column up.

 

Yeah the speedo cable. I already got it though just pushed the latch in haha. I have power coming to my gauge cluster.. I turned all my gauges to 0 and put the gauge cluster back on. As soon as I started it the RPM gauge spiked and didn't come back down & the oil went to 35 and wont go below that but moves a bit. My fuel gauge spiked but came back down slowly to right about the red line. My speedo doesnt work at all. How can I tell if my speedo cable is broken like the connecter pieces. Any clue on how to fix this?

 

Inspect the speedo cable all the way back to the transmission... On mine I replaced the speedo cable and the gear inside the transmission that makes it work( the gear was broken inside the transmission). I went to the bone yard and took the gear off of another 700R Trans. And now it works great. Cant say the same for my rpm gauge... which is always spiked.

 

Ha! Mystery solved. The other day I jacked it up and found its off of my trans. only thing is I cant find where it even goes on.