Depress brake pedal, fuel gauge goes to zero |
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Depress brake pedal, fuel gauge goes to zero |
andrewmlin |
Feb 25 2013, 04:33 PM
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#1
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'74 2.0 Group: Members Posts: 22 Joined: 20-June 11 From: San Bruno, CA Member No.: 13,220 Region Association: Northern California |
I took my '74 2.0 out for a spin yesterday and immediately noticed that something was wrong. The gas light was constantly lit even though I just filled up the tank. Whenever I depressed the brake pedal, the fuel gauge would move to empty. The voltage is reading low (central console). When driving the car, the tach is about half what it should be. The turn signals don't work (or click). However, the car drives just fine. Could this be a fuse or something more serious?
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Black22 |
Feb 25 2013, 05:57 PM
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#2
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Senior Member Group: Members Posts: 886 Joined: 1-November 07 From: Creswell, OR Member No.: 8,290 Region Association: Pacific Northwest |
Damn, this happened to me once too...I can't remember what the fix was...still thinking.
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euro911 |
Feb 25 2013, 07:06 PM
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#3
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Retired & living the dream. God help me if I wake up! Group: Members Posts: 8,849 Joined: 2-December 06 From: So.Cal. & No.AZ (USA) Member No.: 7,300 Region Association: Southern California |
Check the blinker fluid
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oz371 |
Feb 25 2013, 08:09 PM
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#4
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Member Group: Members Posts: 101 Joined: 28-August 09 From: ontario, CA Member No.: 10,739 Region Association: None |
Check the blinker fluid NO no no! Its the muffler bearings. (IMG:style_emoticons/default/icon_bump.gif) |
URY914 |
Feb 25 2013, 08:14 PM
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#5
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I built the lightest 914 in the history of mankind. Group: Members Posts: 120,662 Joined: 3-February 03 From: Jacksonville, FL Member No.: 222 Region Association: None |
Don't use the brakes.
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Chris H. |
Feb 25 2013, 08:55 PM
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#6
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Senior Member Group: Members Posts: 4,030 Joined: 2-January 03 From: Chicago 'burbs Member No.: 73 Region Association: Upper MidWest |
Nice suggestions so far ... (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/slap.gif)
A fuse would just blow...not usually the cause of wonky stuff like that...is your GEN light on? Otherwise could be voltage regulator? |
andrewmlin |
Feb 25 2013, 10:16 PM
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#7
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'74 2.0 Group: Members Posts: 22 Joined: 20-June 11 From: San Bruno, CA Member No.: 13,220 Region Association: Northern California |
Ok, so I checked my blinker fluid, muffler bearings and, for the life of me, couldn't find the trans ground strap. All no-go. Thanks for all the wonderful and helpful feedback though, gotta love these boards (IMG:style_emoticons/default/smile.gif)
What is the GEN light? The only light that is on all of the time is the gas light. I'll check the fuses tonight... |
Valy |
Feb 25 2013, 10:36 PM
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#8
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Senior Member Group: Members Posts: 1,675 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
Ok, so I checked my blinker fluid, muffler bearings and, for the life of me, couldn't find the trans ground strap. All no-go. Thanks for all the wonderful and helpful feedback though, gotta love these boards (IMG:style_emoticons/default/smile.gif) What is the GEN light? The only light that is on all of the time is the gas light. I'll check the fuses tonight... You have a ground problem. I would start with the battery ground to body check/contacts clean. Then move to the ground behind the fuse panel. You may need to undo the panel screws. Make sure the battery is disconnected before taking the panel off. |
andrewmlin |
Feb 25 2013, 10:46 PM
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#9
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'74 2.0 Group: Members Posts: 22 Joined: 20-June 11 From: San Bruno, CA Member No.: 13,220 Region Association: Northern California |
Ok, so I checked my blinker fluid, muffler bearings and, for the life of me, couldn't find the trans ground strap. All no-go. Thanks for all the wonderful and helpful feedback though, gotta love these boards (IMG:style_emoticons/default/smile.gif) What is the GEN light? The only light that is on all of the time is the gas light. I'll check the fuses tonight... You have a ground problem. I would start with the battery ground to body check/contacts clean. Then move to the ground behind the fuse panel. You may need to undo the panel screws. Make sure the battery is disconnected before taking the panel off. Now I can't tell who is kidding and who is not! This sounds like good advice - Thanks Valy. I will check the grounds. |
stugray |
Feb 25 2013, 10:53 PM
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#10
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Advanced Member Group: Members Posts: 3,824 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
the trans ground strap was not a joke and also my first thought.
It is above the tranny and ties the engine to the body. It is usually torn loose the first time the engine is removed by a newb. It also corrodes and gives a poor ground to the engine electricals. Stu |
TheCabinetmaker |
Feb 26 2013, 05:28 AM
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#11
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Check the connection for the reverse lights on the drives side of the trans. Check all fuses, and roll them in their holders. Check the connections on coil too. Make sure the coil is properly mounted too
No jokes here. |
Chris H. |
Feb 26 2013, 06:44 AM
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#12
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Senior Member Group: Members Posts: 4,030 Joined: 2-January 03 From: Chicago 'burbs Member No.: 73 Region Association: Upper MidWest |
Starting with mine the responses are legit although I don't think I was correct. The GEN light is the generator/alternator light. It's a red light in your combo gauge. Was wondering if it was going bad. When the car gets low on juice it does act very strangely...
The grounding issue is probably it. There IS a transmission ground strap which is about a foot long or so and is a flexible piece of flat mesh-like metal about an inch wide. It's attached to the rear of your trans, then to the underside of the rear trunk. As stugray said it gets ripped off commonly because it looks like someone added it after the fact. If you can't find it, well, that's your problem. |
URY914 |
Feb 26 2013, 07:01 AM
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#13
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I built the lightest 914 in the history of mankind. Group: Members Posts: 120,662 Joined: 3-February 03 From: Jacksonville, FL Member No.: 222 Region Association: None |
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ww914 |
Feb 26 2013, 09:01 AM
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#14
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914 Convert Group: Members Posts: 435 Joined: 29-September 11 From: Central Coast, CA Member No.: 13,621 Region Association: Central California |
Is it normal here for a newbie to be treated this way? Obviously, this new member is looking for some electrical help and some of us are treating him like you would a freshman in college. It is obvious the brake pedal needs adjustment as it is hitting the gas tank.
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Chris H. |
Feb 26 2013, 09:15 AM
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#15
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Senior Member Group: Members Posts: 4,030 Joined: 2-January 03 From: Chicago 'burbs Member No.: 73 Region Association: Upper MidWest |
Don't think it's possible for the brake pedal to get anywhere near the gas tank and that would not cause the gauges to go nutty and the other issues. It's most likely a grounding problem or a short. If the grounds are OK you'll want to check for a cut in the wiring harness. Voltage regulator is still a possibility but not as likely.
Do the electrical issues only occur when the brakes are applied? Have the turn signals stopped working permanently? When my battery was dying I got a bunch of odd electrical gremlins temporarily. It was a combination of that and the fact that my generator was not quite strong enough to support the needs of the car. |
toolguy |
Feb 26 2013, 09:39 AM
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#16
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Senior Member Group: Members Posts: 1,268 Joined: 2-April 11 From: San Diego / El Cajon Member No.: 12,889 Region Association: Southern California |
Ok here you go. .What was the last thing that happened just before you noticed the issues. . . did you change anything ??? You said your volt meter reads low. . . . 1st make sure you have a good battery. . 12.5 -13 volts at the battery with the ignition off. . . then check again with the car running. . don't rely on the factory dash voltmeter. .
Easiest way to describe the grounding circuit is to visualize the entire steel body and a huge brown {Ground} wire. . . It ties all the ground circuits together and back to the negative side of the battery. . . Clean the main ground points, but disconnect the battery before starting. . . . they are the battery grd, the trans grd and the ground under the dash above the fuse tray. . there is another ground point above the engine relay panel behind the drivers seat. . . also look at all the connections on the top of the fuse tray at the connection posts , see anything crossed ???? Also above the fuse tray is the main 12 volt common connection, take a look at it but remember it is always hot so it's an absolute must to disconnect the battery unless you want a big flash and fire. . . Sounds like what is happening is one component has a poor ground, and the voltage for that unit is looking for the best ground it can find back to the battery. . . Because it's designed ground has resistance [poor connection], the voltage is back feeding through other circuits and causing those components to appear they are operating / lighting up with the wandering voltage. . If that doesn't do it, you might want to do a visual check of the main wiring harness where it runs above the pedal assembly and enters the front of the inside body tunnel. . I remember a car that the owner drilled down through the panel between the seats to put in a sheet metal screw and went into the wiring harness. . hard to find that issue. . |
Spoke |
Feb 26 2013, 10:22 AM
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#17
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Jerry Group: Members Posts: 6,978 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
Does this happen when you first press on the brake? In other words, does the gauge stop working when the brake light comes on or when you press hard on the brake?
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charliew |
Feb 26 2013, 10:28 AM
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#18
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Advanced Member Group: Members Posts: 2,363 Joined: 31-July 07 From: Crawford, TX. Member No.: 7,958 |
First things first. Look at the battery connections. Both of them. Clean them till they are nice and shiny in the holes of the cables and around the terminals. While the cables are off check the battery condition with a battery checker that checks amperage by applying a drain to the battery. Harbor freight has a cheap one that works. With old cars you will need one anyway. Next check the output of the alternator while the motor is running across the battery. It should be around 13.8 to 14 volts. If all this is good then start checking the grounds starting under the car where the ground strap connects to the tranny. Actually like the others said all the grounds need to be cleaned to avoid any more surprises. But also the 12 v connections should also be replugged and checked for looseness or over heating. Old stuff needs a checkup at least every few years especially the parts under the car that are usually neglected. Your car will teach you how to be a better mechanic or encourage you get a better paying job so someone else can deal with it.
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rgalla9146 |
Feb 26 2013, 11:00 AM
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#19
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Advanced Member Group: Members Posts: 4,554 Joined: 23-November 05 From: Paramus NJ Member No.: 5,176 Region Association: None |
Does this happen when you first press on the brake? In other words, does the gauge stop working when the brake light comes on or when you press hard on the brake? The last couple responses are absolutely correct. One more thing though, o you know which is your warning lamp for charging ? With the ignition on,(engine not running) you should have warning lamps lit for oil pressure, charging and hand brake ( if it's on ) If you don't see the charging light you need to remedy that first. |
andrewmlin |
Feb 26 2013, 11:39 AM
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#20
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'74 2.0 Group: Members Posts: 22 Joined: 20-June 11 From: San Bruno, CA Member No.: 13,220 Region Association: Northern California |
Thank you everyone for the advice. Last night, I removed and cleaned all of the fuses in the box, then turned the ignition - everything fixed! I guess there was just a weird connection or some corrosion happening.
However, really good advice on checking/taking care of all the grounds. This weekend, I will do this to prevent further complications. Thanks again! |
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