Fuel pump "cycles" when turn signal is on.

[1QWIK6]

I can hear my fuel pump "cycle" with the turn signal. What causes this?

I have I have Red Double pumper and a hot-wire kit. Battery is 3 years old and voltage on the scanmaster is 13-2-14V. I have my battery ground going to the downpipe too.


Thoughts?

 

[mikestertwo]

That's normal. Just the extra load from the lights slightly dropping the voltage.

 

[jurassic five 7]

How is that normal? Please explain a little. When the turn signals are on, i dont hear anything from the fuel pump? Even if the radios up, the brights are on, and im using the signals, there is no 'cycle' of fuel pump?

-Daized and Confused-
Adam

 

[Boost231]

there has to be something else going on. i have never heard my pump do this with the turn signals.

 

[1QWIK6]

there has to be something else going on. i have never heard my pump do this with the turn signals.

I thinking bad ground, but I have a new(er) negative cable going to the downpipe. So that should be a strong ground. Plus with a hotwire kit, I think the pump would have normal voltage at all times.

Thoughts?

 

[LC2BUICK]

Problem appears to be a ground. But not your main ground that you spoke of. Check your body grounds. I would start in the rear of the car. Trace back you fuel pump ground to the ground point. This will be a good place to start.

 

[garyk1970]

check the ground inside the trunk under the drivers tail lamp,fp and lights ground there.

 

[1QWIK6]

Problem appears to be a ground. But not your main ground that you spoke of. Check your body grounds. I would start in the rear of the car. Trace back you fuel pump ground to the ground point. This will be a good place to start.

Any idea where the f/p ground is?

 

[garyk1970]

check the ground inside the trunk under the drivers tail lamp,fp and lights ground there.

cant miss it.pull the trunk carpet back to access.

 

[Chuck Leeper]

What???

"I have my battery ground going to the downpipe too." Huh??
Why would you run a ground that way?
Lets see:
1. Grnd cable to DP bolt = connection #1.
2. Dp to turbo = connection #2.
3. Turbo to header = #4.
4. Header to engine cyl head = 5.
And, to top it all off, the dp is a good source of heat in the 1500* range.

I guess I'm missing something, here.

 

[Chuck Leeper]

Not if..

I thinking bad ground, but I have a new(er) negative cable going to the downpipe. So that should be a strong ground. Plus with a hotwire kit, I think the pump would have normal voltage at all times.

Thoughts?

as mentioned, you have ground issues. The best power wire in the business is worthless if the grounds are FUBAR...

 

[87geeinn]

"I have my battery ground going to the downpipe too." Huh??
Why would you run a ground that way?
Lets see:
1. Grnd cable to DP bolt = connection #1.
2. Dp to turbo = connection #2.
3. Turbo to header = #4.
4. Header to engine cyl head = 5.
And, to top it all off, the dp is a good source of heat in the 1500* range.

I guess I'm missing something, here.

x 2

Most people underestimate the importance of good electrical grounding. Just because metal is touching metal, doesn't mean the ground is good. You've created all kinds of resistance with those numerous contact points. You'd be surprised at all of the electrical gremlins that will surface when ground points are not 'solid'.

 

[mikestertwo]

I thinking bad ground, but I have a new(er) negative cable going to the downpipe. So that should be a strong ground. Plus with a hotwire kit, I think the pump would have normal voltage at all times.

Thoughts?

I missed this in your original post. Why to the down pipe?

 

[1QWIK6]

"I have my battery ground going to the downpipe too." Huh??
Why would you run a ground that way?
Lets see:
1. Grnd cable to DP bolt = connection #1.
2. Dp to turbo = connection #2.
3. Turbo to header = #4.
4. Header to engine cyl head = 5.
And, to top it all off, the dp is a good source of heat in the 1500* range.

I guess I'm missing something, here.

How does heat effect the ground? Isn't the cable copper? Isn't that the material used as a gasket for the header-to-turbo?

 

[mikestertwo]

How does heat effect the ground? Isn't the cable copper? Isn't that the material used as a gasket for the header-to-turbo?

Your using the ground cable as an electrical conductor not a gasket. The heat will oxidize the copper and increase it's resistance giving you poor electrical contact. Do you still have the ground going from the battery to the block?

 

[LC2BUICK]

How does heat effect the ground? Isn't the cable copper? Isn't that the material used as a gasket for the header-to-turbo?

The hotter the copper wire gets the less conductive it will be. Not to mention the copper will turn soft and show signs of discoloration. This is NOT a good ground for the vehicle.

The best way to run a main ground from the battery is to have it go to 3 separate points.

#1 gauge 8 or 10 to the fender or body point
#2 gauge 1 or 2 to main frame, make sure the metal is clean @ this connection
#3 gauge 1 or 2 to engine, preferably the block not the head

Make sure that you use "Good" quality wire for your grounds. Just because the wire is thick does not mean that it is a good wire. The integrity of a wire cable is measured by the strands. The more stands in the cable the better the electric will travel through it.

 

[1QWIK6]

Your using the ground cable as an electrical conductor not a gasket. The heat will oxidize the copper and increase it's resistance giving you poor electrical contact. Do you still have the ground going from the battery to the block?

No.

I will change that now.

 

[1QWIK6]

The hotter the copper wire gets the less conductive it will be. Not to mention the copper will turn soft and show signs of discoloration. This is NOT a good ground for the vehicle.

The best way to run a main ground from the battery is to have it go to 3 separate points.

#1 gauge 8 or 10 to the fender or body point
#2 gauge 1 or 2 to main frame, make sure the metal is clean @ this connection
#3 gauge 1 or 2 to engine, preferably the block not the head

Make sure that you use "Good" quality wire for your grounds. Just because the wire is thick does not mean that it is a good wire. The integrity of a wire cable is measured by the strands. The more stands in the cable the better the electric will travel through it.

Thank you for the info. I guess I wasn't thinking.