another alternator question

[BryceComstock]

aloha i know that theres a million alternator threads, but couldnt find any like this issue, this is an 88 3.2 all stock. when i start car starts fine runs fine and no red light. it could idle all day with no red light. as soon as you rev motor the red light comes on. and stays on. just started so dont know if its effecting charging or not but kinda wierd. you can turn off ignition and restart. same issue every time. any ideas?

[BryceComstock]

OK now my guages are acting up, sporadic, tach oil pressure dead until you rev it up.any ideas?

[S2GART]

Check your VR. Get a basic voltmeter and check your battery voltage with the car off. It should be about 12.5-12.8. Start the car, the voltage should then read about 14.5, but no more than that. If it still reads near the 12.5, then you alternator isn't charging. If it reads higher then the voltage regulator is faulty. Also, rev. the engine to about 1500 rpms, and the volts should stay at 14.5.

[BryceComstock]

thanks i will check but why would it make all my guages freak out?

[EdT82SC]

Freaky gauges could be too high of voltage caused by bad voltage regulator. That is where I would start.

[yanik]

It actually should be no more than 14.2... just on idle...

[S2GART]

When I had what turned out to be a bad VR, my tach would periodically bounce and at the same the Fasten Seat Belts light would come on every time I accelerated. Another way to look at what a VR does is that it restricts/limits the voltage coming out of the alternator.

[VMAX1]

Check out this cheap gadget. Was lucky to have this a while age. Alt light would come on and go out with a little rev at start up. Well, Alt light stopped coming on and my little cig. plug in was telling me she wasn't charging, and it was not charging. Light can come on or not when alt. is not charging. INNOVA 3721 Battery and Charging System Monitor | eBay Just something I like to have.

[rpc356]

I had bought one of those plug in gadgets a few months ago based on seeing comments on the forum. Just a couple weeks ago it identified low charging voltage where the idiot light was not coming on. Would eventually have killed the battery and no doubt gotten me stuck somewhere if I hadn't seen the problem via the plug in monitor (turns out the alternator was bad). Handy gadget.

[BryceComstock]

sorry guys got kinda busy, i pulled alternator thinking for sure had to be either or alt, or vr, but both were good. the only other thing is my fuel guage was not installed completely in dash so i installed it thats when things started going haywhire, now no turn signals along with freakin out guages. does anyone have a scematic of the fuel guage wiring.

[pors1968]

Did you check the ground on your gage the ground is important on gage.

[BryceComstock]

yes ground is ok. there are two relays behind the fuel slash oil guage. the one all the way to the left is extremely hot what does that go to

[BryceComstock]

relay says. fensterheber 944.615.116.00- 89 83 29 12v 40a

[BryceComstock]

sorry guys bare with me here but i just found a brown with a white stripe wire with the end broke off kind behind the left two guages, but dont see where it came from any ideas. i dont have any schematics sorry

[BryceComstock]

Anyone have an idea

[BryceComstock]

aloha guys, ok this is a lesson with starting from basics first. all this headache and all it was ,was a bad connection on a fuse. crazy... thanks for advice

[GH85Carrera]

Thanks for posting the final fix. That really helps when future search brings up this thread.