electrical problem, Lights diming?

[goldeninja20]

I have the car running with nothing on at all. I have a walbro fuel pump that is rewired. When i turn on my blinker on, my fuel pump makes a different tone, like it is stuggling for power. My lights on the dash flash also. My battery and alternator are both tested fine. I sanded my ground from my battery to firewall. What else could be my problem.

 

[oh-b-1g]

There is also a ground from your engine to the chassis. A lot of people forget about that one when diagnosing electrical problems.

I would check the grounds under the dash near the steering column too just in case. And double check the fuel pump wiring is securely soldered, mounted, and not rubbing on anything

 

[goldeninja20]

There is also a ground from your engine to the chassis. A lot of people forget about that one when diagnosing electrical problems.

I would check the grounds under the dash near the steering column too just in case. And double check the fuel pump wiring is securely soldered, mounted, and not rubbing on anything

I will be checking the fuel pump wires but the lights also dim too. I didnt know there should be any grounds under the dash. What needs to be grounded? Also my brake lights cause the lights to dim and a change in fuel pump sound.

 

[miguelmcv]

All the dimming light thing is because starving of current.

Check your alternator Fuse, located at the engine fuse box.
Check all your grounds as well, There is one behind the radio, it is almost on the same location where the Automatic ECU use to be.

Check if your alternator is making good ground to the block, you can add ground by bolting on a wire from the alternator to the block and/or to the chasis.

How did you test the alternator and Battery?.
Did you take it to any autopart, or you tested by your self, If you took it to the autoparts, then it might be your alternator that is not working.
Alternators will pass the test at autorpart, but once they are installed and on heavy load, they fail.
You need to test it by your self with the engine ON and warm.

 

[goldeninja20]

Everything seems to be fine. It cranks very good. I will add a ground on the alternator to see if that may improve the problem. They were tested by a shop. I will be checking out that ground brhind the radio tommorrow. I know i have the starter relay ground behind there also.

 

[oh-b-1g]

I will be checking the fuel pump wires but the lights also dim too. I didnt know there should be any grounds under the dash. What needs to be grounded? Also my brake lights cause the lights to dim and a change in fuel pump sound.

Its almost certainly a ground. There should be a bundle of black wires under the dash that all terminate into eyelets and should be bolted to a bracket near the steering column. Did you find the engine to chasis ground? That is the main ground link to complete the charging circuit between the alt. and the battery. If its loose it'd be like trying to suck peanut butter thru a straw for the current to pass through, thus giving you the weak current.

 

[goldeninja20]

i did some more research on the problem today. I added a ground from the alternater to chassis. This made no difference. it seems as though only my binkers and brake lights are causing flickering and a change in fuel pump sound. I have a 12 inch 500rms subwoofer. When im bumping hard it does not affect anything. I imagine my sub should be using more power than a blinker. Is there a specific ground for the tail lights that i could be missing?

 

[miguelmcv]

There is a ground wiring at the back in the trunk, right under the latch, remove the middle section and you will see it, it screws in via a screw.

 

[goldeninja20]

I found it. It was still connected, looks like it was never taken off. I took it off, sanded it a little better, put it back on and no difference. Is there any other grounds, The problem still consists with the car off and radio and everything turned off. The lights will still flicker. Should i even worry about it?

 

[miguelmcv]

The only ground left is at the battery location, it goes from the battery to the firewall, and the other one, is attached to the firewall very close of the theft alarm horn, right aside of the ground mentioned before.

Check those, but it sounds like your alternator is not holding on, I used my car like that for a month, until I got tired of the freaking noise of the pump and I replaced my alternator and it fixed my problem.

You said the alternator was tested, But test it your self, believe me, just test it and report back the results.

 

[goldeninja20]

What power should the alternator be putting out at idle (~1000rpm)

 

[miguelmcv]

At least it has to be 13v, or over that, If it is 12v, then your alternator is no good.

 

[goldeninja20]

Ok ill check it tommorrow. I will get back in the morning.

 

[miguelmcv]

Sorry, forgot to mention, test the volts at the alternator outlet, then check the same line at the fuse box, It has to show the same volts, if it doesn't show the same volts, then the alternator wire is not good, after you test on both places, check the volts at the battery as well to see how many volts it has, it should be the same as the alternator.

 

[goldeninja20]

I was considering the wire to be a problem. I will most likely replace it with a 4 gauge wire.

Its almost certainly a ground. There should be a bundle of black wires under the dash that all terminate into eyelets and should be bolted to a bracket near the steering column. Did you find the engine to chasis ground? That is the main ground link to complete the charging circuit between the alt. and the battery. If its loose it'd be like trying to suck peanut butter thru a straw for the current to pass through, thus giving you the weak current.

I also cant seem to find any grounds under the dash, im thinking that may be the problem. Does anyone know or have a diagram of what wires should be ground? There is a mess of wires because the owner before me had an alarm there and cut all the wires.

UPDATE! Alternator is pushing out 14.2 volts. the battery is reading 13.8 and the fuse is reading 14. this doesnt seem too bad but i am still considering using 4 gauge wire.

 

[goldeninja20]

NO PROBLEMS WITH BATTERY OR ALTERNATOR OR WIRE. My problem is still occuring, is it something i should worry about? There must be a set of grounds somewhere that i cannot find. Someone said under the dash but i do not see any nor do i see any dangling or hanging.

 

[miguelmcv]

Let's clear this up, you have checked (Ground).
At the battery (from battery to transmission),
At the battery (from battery to Firewall),
At the Firewall (right a side of your Alarm Horn next to battery ground firewall),
At the back of the ECU (where the Automatic transmission ECU location),
At the driver side fender (there is a multiple ground under the driver side fender),
At the back of the trunk (right under the latch).

Please specify which you have checked and which you haven't, make sure you clear this up so we can discard them.

 

[goldeninja20]

Let's clear this up, you have checked (Ground).
At the battery (from battery to transmission),
At the battery (from battery to Firewall),
At the Firewall (right a side of your Alarm Horn next to battery ground firewall),
At the back of the ECU (where the Automatic transmission ECU location),
At the driver side fender (there is a multiple ground under the driver side fender),
At the back of the trunk (right under the latch).

Please specify which you have checked and which you haven't, make sure you clear this up so we can discard them.

-At the back of the ECU (where the Automatic transmission ECU location),
-At the driver side fender (there is a multiple ground under the driver side fender)

THESE are the 2 i have yet to check, From battery to firewall I have 2 gauge wire, and from battery to transmission i have 4 gauge wire. BOTH these sanding points have been sanded to bare metal.

 

[Bojangles465]

you could have some back feeding somewhere, but your guess is as good as mine, i say just do some testing with a multi meter

 

[goldeninja20]

you could have some back feeding somewhere, but your guess is as good as mine, i say just do some testing with a multi meter

i have tried alot. still cant figure it out.

 

[goldeninja20]

bump... still having the issue. Hasn't got worse but brake lights and blinkers seem to make my check engine light dim and affect idle very slightly.

 

[Bojangles465]

try rewiring the grounds directly to the negative terminal on your batery, its worth a shot

 

[thearkatek]

Ya I would say try hardwiring some of your grounds together, even if just temporarily. Seems silly, but it's easy enough to do and you might as well try if you've got some spare wire left from the fuel pump rewire.

 

[goldeninja20]

Ya I would say try hardwiring some of your grounds together, even if just temporarily. Seems silly, but it's easy enough to do and you might as well try if you've got some spare wire left from the fuel pump rewire.

I have alot of grounds and still doesnt seem to solve the issue.