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Running hot, odd connector

Slrmclaren2006

New member
On the back of the motor, i have a 2000 Grand Prix GT 3.8 and in the wire harness coming off the O2 sensor in back on rear exhaust manifold, near alternator, there's a plug that nothing is going to it, seems odd to just have a plug there for no reason. If car heats up beyond normal with A/C on and water pump is replaced and thermostat and coolent level is fine, what could be issue?
 


Re: 3800 supercharged.. grand prix

On the back of the motor, i have a 2000 Grand Prix GT 3.8 and in the wire harness coming off the O2 sensor in back on rear exhaust manifold, near alternator, there's a plug that nothing is going to it, seems odd to just have a plug there for no reason. If car heats up beyond normal with A/C on and water pump is replaced and thermostat and coolent level is fine, what could be issue?

Are the fans coming on?
 
fans come on fine. Now before all this, someone rewired the fans to where one fan was blowing the wrong way, the car shop "fixed that" and replaced the water pump cuz the fins somehow broke on it. and they replaced the thermostat from what i was told. the fans come on right when u turn the key on, be4 the car even starts up. so i know those work.
 
Fans shouldn't be coming on until after the tstat opens and the motor heats up to a certain temp. If they come on before you even start the car then there is a problem.

Can you take a picture of the connector? How many wires are going to it?
 
yeah i dont know why fans on coming on before hand, actually drains my batterty if left on for like 5 mins, car barely starts and when it starts, the idle kinda bounces for a min and then smooths out. and when i do start the car, dash lights and all else are dim, then suddenly brightens up. ill take pic of the connector. its two wires going into it, and its part of the wire harness coming off the rear O2 sensor.
 
idle bounces for a sec* a new problem i've been having, engine light is coming on now. tells me my problem is the same as before. cylinder 4 misfire. which is BS cuz i replaced wires and plugs. I was told, that maybe that connector being unplugged might be messing with the O2 sensor causing the engine light once the car is driven for so long. but i figured the fuel injectors were dirty, so i went on freeway, pedal was floored the whole time for like 15 miles, engine light went off. So weird.
 


Forget about the connector. It's supposed to be there and not plugged into anything...same on my 2000 GT. Make sure there is a 2 wire connector on the upstream O2 sensor. If it's there and the wiring looks good then forget about it.

Your fans are hardwired - need to un-hardwire them. Make sure someone hasn't put a jumper at the relay box. You say shop "fixed" that? So they manipulated the incorrectly wired fan circuit just to make the fans spin in the correct direction? W-T-F

Get this taken car of first then we can work on the overheating issue.
 
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Hey! I looked at the fan wires and i think there is a jumper right there. I hate dealing with electrical so this isnt really my field. But, i cant think of what its called, but when u have a wire going in each end and its crimped, well theres a wire going from the fan back through the firewall and i think its for my stereo deck. Cuz at high volume, it cuts out and never at low volume. Weird because anything with stereo should be running off the batterty. I took two picts of that and a picture of that extra wire in the back coming off the upstream O2 sensor. Theres also an extra plug near the fuse box in the bottom coming out of the wire harness. If i can attach the pictures you will understand.
 
Alright. Photos are public so you should be able to view them. I think i may just go to an audio shop, have them unwire the stereo wire and re wire the fans back to normal.
 
Idk if you can view those 3 attached photos or not. Idk how this works all that well. But, just in case.

https://www.facebook.com/photo.php?...88159671.86778.100000240284594&type=3&theater

https://www.facebook.com/photo.php?...88159671.86778.100000240284594&type=3&theater

https://www.facebook.com/photo.php?...88159671.86778.100000240284594&type=3&theater

Those are the links to the 3 photos i took. Hopefully that explains more.

In the first and second pics, it looks like someone tapped ino the wiring for the ambient temperature sensor.?.?
Those are not your fan wires.
It looks like a fuse splice. BTW those things are called crimp connectors. There are many different types.
You've got to find where these wires go and remove them. They may be reused if wired properly to the fuse panel or the battery.
Reattach the original ambient temperature sensor wires using new cripm connectors and seal them with shrink tubing.

The last pic is the one you don't have to worry about.
The other unused connector near the fuse panel is OEM and many people have the same thing. I wouldn't worry about that one either.

A description of what modifications are on the car will help determining what the last person did with the wiring.
What the heck is that gauge laying on the subframe?

It looks like someone either:
Tapped into the ambient temp sensor wires to power the head unit
or
Tapped into the ambient temp sensor wires to trip the fan relays

Also, check the fan wiring for spliced wires.

People think they can just splice into any wires on these car...NOT!
 


Hmm don't know about that first one but the rear one looks like a fpr connector, there were some extra emissions stuff on some years that might have been removed before you got it. Only other thing I can think of it being would be for the brake fluid level but if you have a connector on the master cylinder already then you are all set.
 
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