RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   Fuel Level Connector (https://www.rx7club.com/1st-generation-specific-1979-1985-18/fuel-level-connector-1080569/)

Jere Urso 03-21-15 11:56 AM

Fuel Level Connector
 
1 Attachment(s)
As you can see the connector has corrosion and this is before I cleaned it up pretty good. The corrosion changes the resistance going to the fuel gauge giving me different responses of the fuel level. After I cleaned it up it went back to what it use to be for a while but after I washed my car last night and spraying that area it went back to changing levels and dropping below empty in a matter of minutes.

Jere Urso 03-21-15 11:59 AM

3 Attachment(s)
These pictures were taken in less than 10 minutes. This was last night.

Jere Urso 03-23-15 06:36 AM

Anybody know how to clean this connector up or have the same issue as me before?

DivinDriver 03-23-15 10:01 AM

There's supposed to be a plastic inner fender piece between the wheel well and the tank/sensor. Likely you'd have less trouble with this if that piece was where it's supposed to be.

Jere Urso 03-23-15 10:40 AM


Originally Posted by DivinDriver (Post 11889349)
There's supposed to be a plastic inner fender piece between the wheel well and the tank/sensor. Likely you'd have less trouble with this if that piece was where it's supposed to be.

Well damnnn.

t_g_farrell 03-23-15 12:06 PM

Also, the sensor gets its reference for ground through the round base that it mounts to. Over
time the contact between the base and outside part of the sensor that connects to the base for
that ground gets weak, so the resistance goes up. The way the gauge works is the higher the
resistance value, the more towards empty the needle points.

You can fix this without remove the sensor from the tank. You need to ground the base of the
sensor to the round base that bolts the sensor assembly into the tank. I did this by running a
wire from the sensor base and putting it under one of the mounting screws.

Jere Urso 03-23-15 08:12 PM

I'll try to whip something up so it works on Wednesday, thanks.

Jere Urso 03-24-15 03:13 PM


Originally Posted by t_g_farrell (Post 11889414)
Also, the sensor gets its reference for ground through the round base that it mounts to. Over time the contact between the base and outside part of the sensor that connects to the base for that ground gets weak, so the resistance goes up. The way the gauge works is the higher the resistance value, the more towards empty the needle points. You can fix this without remove the sensor from the tank. You need to ground the base of the sensor to the round base that bolts the sensor assembly into the tank. I did this by running a wire from the sensor base and putting it under one of the mounting screws.

Could you get a picture of this setup, if possible?

Jere Urso 03-25-15 10:34 AM

Found out it was a bad ground, had the same idea that you had and did the same thing but ran outta time to finish it.

Jere Urso 03-26-15 03:29 PM

5 Attachment(s)
Well got it all working, but two things, it tells my my real fuel amount when the key is turned with the dash lights on but when I start the car the gauge drops down about 1/4 tank of what the real fuel amount is and the fuel light stay on and blinks (from fuel moving around?) Maybe it'll fix itself or something lol but I got it all working just there is a bug to it. Anybody have ideas of what this little bug could be?

j9fd3s 03-26-15 04:36 PM

250 Connectors

DivinDriver 03-27-15 04:35 PM

1 Attachment(s)
Here's the panel you're missing, for future reference:
https://img.photobucket.com/albums/v...327_120937.jpg

Here's where it goes:
Attachment 627931

Jere Urso 03-27-15 07:40 PM


Originally Posted by DivinDriver (Post 11891681)
Here's the panel you're missing, for future reference: Here's where it goes:

Thanks.
My fuel light still stay stays on and now my gauge reads the same with the key on and when the car is started but I have a full tank and the fuel light stays on.

Jere Urso 03-29-15 09:03 PM

Well, found out that my ground caused parasitic load and my battery is now low and won't start my car so I threw it on the charger. Disconnected my ground until I figure out what's going on. Does anybody know how this fuel sending unit is wired or ever looked at the inside of it to help me out because I need it.

woodmv 03-29-15 09:08 PM

DivingDriver did a write up on modifying an FB fuel sending unit to work on an SA. It's around here somewhere and is a good read with lots of pics and specs

Jere Urso 03-29-15 09:12 PM


Originally Posted by woodmv (Post 11892831)
DivingDriver did a write up on modifying an FB fuel sending unit to work on an SA. It's around here somewhere and is a good read with lots of pics and specs

Can you send me the link I'm on my phone and can't find it.

Jere Urso 03-29-15 09:21 PM

But at the same time this doesn't make sense because if it was causing parasitic load wouldn't the gauge be reading with the key off?

woodmv 03-30-15 10:35 AM

Its in the archives section:

https://www.rx7club.com/1st-gen-arch...sender-786986/

Jere Urso 03-30-15 11:07 AM

So while reading that, my ground wire has to be ground to the rivet in the middle of the baseplate and its not. That must be the reason it's all screwy, now I gotta figure how to get a good attachment of my ground on that corroded rivet.

Jere Urso 03-30-15 03:42 PM

Does anybody know if this is correct?

DivinDriver 03-30-15 05:16 PM


Originally Posted by Jere Urso (Post 11892832)
Can you send me the link I'm on my phone and can't find it.

https://www.rx7club.com/1st-gen-arch...sender-786986/

t_g_farrell 03-31-15 07:58 AM


Originally Posted by Jere Urso (Post 11893132)
So while reading that, my ground wire has to be ground to the rivet in the middle of the baseplate and its not. That must be the reason it's all screwy, now I gotta figure how to get a good attachment of my ground on that corroded rivet.

Yep, this is what I was referring to. I think I might have soldered it on there. Can't
remember now and then tucked the other end under one of the screws holding
the assembly to the tank.

Jere Urso 04-08-15 09:27 AM

1 Attachment(s)
Well, now its actually all working, after cleaning the copper contact where the old ground broke off I basically just dumped solder between the two connections to make sure it wouldn't break free. After I took this picture I heat shrunk electrical tape over the connection. If corrosion ever eats your ground for your fuel level sender, this is something you could do.

Jere Urso 04-15-15 10:00 AM

Would the low fuel light come up if the gauge doesn't work? If the light illuminates with the others before starting means the connection is good? The ground must not be good enough because the gauge on the dash just quit working after a week of working lol Such a pain.

Jere Urso 04-17-15 09:33 AM

Anybody know? I've been looking at schematics of the wiring but it doesn't really show the fuel level sender very good.


All times are GMT -5. The time now is 01:36 AM.


© 2024 MH Sub I, LLC dba Internet Brands