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1986 4+3 questions

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Old Oct 6, 2012 | 02:57 PM
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Default 1986 4+3 questions

Hi all. I just got my vette and have a few issues I was hoping the community might be able to help with. I have to order an owner's manual as the prior owner didn't have one.

1. The power seats don't work at all. I find it strange that both motors would've gone bad. I checked the fuses and can't find one labeled for the seats (the power door locks don't work either if that helps but the windows do, albeit VERY slow to raise)
2. The AC doesn't work. The fan blows but it doesn't seem like the compressor is kicking on.
3. The oil temp seems to be somewhat high, peaking at 230*. Is that normal?
4. I'm not sure if the overdrive is working correctly. On the highway going 65-70PMH, the overdrive light on the center of the dash is on, but the RPMs seem WAY too high at almost 3k RPM. I push the button on the top of the gear shifter and that light goes on and off, but the RPMs don't change.
5. The brake pedal is very spongy on the first depression and then firms up and the car stops great. From what I've read, it could be a master cylinder issue but a friend of mine suspects the brake fluid might have degraded and the whole system should be flushed. The former owner drove the car sparingly over the last 10 years...something like 8000 miles. The windshield has an "next oil change" sticker on it from 2007 saying the next change should be at 74.5K miles....I bought the car yesterday with 72K. .

Any and all suggestions are most appreciated. I'm new to this and can do a few things mechanically but not alot. I'm patient and can follow good directions too. I'm just trying to not get robbed by some mechanic.

Thanks,
Joe
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Old Oct 6, 2012 | 06:48 PM
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Originally Posted by MJC2X
I'm not sure if the overdrive is working correctly.
I push the button on the top of the gear shifter and that light goes on and off, but the RPMs don't change.
If last service unknown then change fluid and filter in the O/d ; low fluid will prevent operation
Check the wire running to the O/d , often connection at unit is broken or loose
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Old Oct 7, 2012 | 09:04 AM
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http://members.shaw.ca/agent86/Power%20Seats.pdf

http://members.shaw.ca/dankai/HVAC%20Electrical.pdf

http://members.shaw.ca/dankai/HVAV'S.pdf

http://members.shaw.ca/agent86/Power%20Door%20Locks.pdf

http://members.shaw.ca/agent86/Overdrive-manual.pdf
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Old Oct 8, 2012 | 12:55 PM
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Originally Posted by rodj
If last service unknown then change fluid and filter in the O/d ; low fluid will prevent operation
Check the wire running to the O/d , often connection at unit is broken or loose
Thanks. I have 2 neighbors with Vettes and they recommended an honest, local guy to do the basics for me. I dropped it off to him today. They also recommended a place in Brick, NJ (Anger Management Racing), if the 4+3 ends up being a bigger problem. Thanks for all the input guys.
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Old Oct 12, 2012 | 06:11 PM
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HELP!!!! I went to autozone to buy some fuel injector cleaner. When I came out, I unlocked the car and an alarm that I had no idea was there started going off. It's a steady horn beep for 2 or 3 minutes and then it stops and doesn't come back on again. I'm able to start the car with no issues and the alarm continues to honk. There is no after market alarm installed that I'm aware of. Any thoughts guys? Is this a stock thing on that era vette?
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Old Oct 12, 2012 | 07:34 PM
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Unlocking the driver or passenger door with the key should disarm the horn alarm. Try the passenger door if the driver door is having problems.

If you are having an issue with the switch connected to door lock, that disarms the alarm, don't lock the door with the power locks, as that arms the system.
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Old Oct 12, 2012 | 07:55 PM
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Originally Posted by AGENT 86
Unlocking the driver or passenger door with the key should disarm the horn alarm. Try the passenger door if the driver door is having problems.

If you are having an issue with the switch connected to door lock, that disarms the alarm, don't lock the door with the power locks, as that arms the system.
I just went into my garage and tried both doors. No luck
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Old Oct 12, 2012 | 09:39 PM
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probably not a great time to roll up the windows................
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Old Oct 12, 2012 | 09:54 PM
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Originally Posted by coupeguy2001
probably not a great time to roll up the windows................
Honestly, I would be happy to just disable the system. I don't need the power door locks and I'm rarely, if ever going to park it somewhere it could be broken into or stolen
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Old Oct 13, 2012 | 08:20 AM
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Originally Posted by MJC2X
Honestly, I would be happy to just disable the system. I don't need the power door locks and I'm rarely, if ever going to park it somewhere it could be broken into or stolen
You can disable the horn alarm by cutting the input from alarm controller to horn relay, at the horn relay or at the controller.

The horn relay is behind the info panel and the controller is tucked under the passenger side dash, near the ECM.




Here is some info on the alarm, first part of this file from my 86 FSM.

http://members.shaw.ca/dankai/Vats%20Electrical.pdf
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Old Oct 13, 2012 | 10:36 AM
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There was a guy I met had problems with the hatch switch. His alarm would go off, and he would open the hatch, slam it shut, and then lock and unlock the doors.
If that is the case, you need to determine if the hatch switch is faulty or out of adjustment.
Just that everybody forgets the hatch because it's almost impossible to breach the car through the hatch, and it is on the alarm.

When I first got my 86, my wife and I went to the mountains and we stopped to get gas, I was still trying to find her jacket in the back after I locked the doors and shut them. I almost got the jacket out, when the horn started honking.
At first, I thought I hit something when her shoes tumbled out of a plastic bag and one hit the instrument panel.
I went over to the door, and realized I locked the door. I got out my key, and unlocked the door with the key, and the horn stopped going off. That's when I found out it had an alarm, and it was tied to the hatch, because that was the only thing that was open.

There is an approx. minute or so delay before the alarm sets, so you can get out, unload something out of the back and shut all the "doors"

Last edited by coupeguy2001; Oct 13, 2012 at 10:41 AM.
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Old Oct 13, 2012 | 11:11 AM
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I disconnected the battery and reconnected it and it stopped. I just have to remember to not use the power locks anymore. Thanks to all
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Old Oct 13, 2012 | 08:43 PM
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AGENT 86 Is the starter re-lay under the dash on the passengerside? I'm having trouble my car won't do anything when I turn the key. TIA:It's an 85 4+3
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Old Oct 13, 2012 | 08:59 PM
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Originally Posted by BV85
AGENT 86 Is the starter re-lay under the dash on the passengerside? I'm having trouble my car won't do anything when I turn the key. TIA:It's an 85 4+3
Starter relay is behind info panel. Look at the pic I posted above.
85's theft deterrent controller also controls the starter relay.
You may want to try unlocking both doors with the key and see if that gets you cranking.
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Old Oct 23, 2012 | 10:40 AM
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So I finally brought my 86 into the transmission expert. My buddy has a 77 and recommended a guy local to him in Jackson NJ. I spoke to him on the phone and he has done lots of 4+3s. He dropped the pan on the overdrive unit and found parts in the pan. He said there was no metal, but pieces of other parts from inside (kind of explains why it wasn't working). Anyway, he's going to let me know today but it sounds like my LOW number is going to be $1200 and depending on how bad it is possibily over $2000. Needless to say, I'm less than thrilled. At the high number, that puts me $6000 into this car. I guess I'm OK with that as the body/paint are very good and it only has 72K miles. I'm hoping that's the end of the big numbers for a while. I wanted to put a new exhaust system in but that's out the window for now.
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