KOEO running noise?

[GNasty]

My buddy put a new positive battery cable on my car; it was easier for him, since he has a lift. The negative cable was replaced last year.

Now, with the key-on, engine off, I hear a loud buzzing/whistling noise, as if something is running. This is clearly coming from under the hood. The fuel pump runs for a few seconds and then shuts off like it normally does - I've had a hot wire kit on for years.

I've had vacuum brakes for years, and I disconnected the relay for the power antenna years ago, after it broke and it was buzzing with the car off. So that eliminates two more possibilities.

I also disconnected the IAC and stock boost solenoid. I can still hear this running sound!

Is this something related to the starter? Starter solenoid? What could he have screwed up by putting on a new battery cable?

The car runs completely fine if started and driven around. Please help...I'm running out of things to unplug...

 

[earlbrown]

Start pulling fuses one at a time. When the buzzing stops, you'll have a pretty good general direction to search.

 

[TLIMITED]

Is it the a/c- heat blower motor?

 

[captndave737]

My guess would be the blower motor with a leaf stuck in it but like earlbrown says start pulling fuses.

 

[earlbrown]

the blower motor shouldn't turn as long as the top climate control slide is set to 'off'.

 

[GNasty]

I pulled the FP/INJ fuse, and the buzzing/whistling noise stopped. I must have an injector stuck open.

I'm not sure why the noise completely stops when the key is turned off. I would think it would continue to leak down for a bit longer, but it doesn't.

I listened to each injector one by one, with a hose to my ear, and couldn't tell which one was the problem.

This weekend, I will disconnect each injector one by one, with the key on, and see which one is the problem.

 

[Chuck Leeper]

If there's an inj "stuck open", look for fuel to be running out of the exh, into the pan..
DO NOT attempt starting the engine, until you find out what is going on.
Hook up the fp ga, prime the system, shut the key off. Psi fall immediately?
Pull the plugs, kill the ign, spin it over. Fuel shooting out?

Bottom line: Unless the fuel pump is continuing to run after the prime cycle, the "leaky inj" theory is not valid.

 

[GNasty]

Chuck, you cleaned and balanced these injectors YEARS ago for me. I appreciate all your help!

Please help me understand your statement below:

Bottom line: Unless the fuel pump is continuing to run after the prime cycle, the "leaky inj" theory is not valid.[/QUOTE]

I thought the fuel pump primes for two seconds and then shuts off, regardless. How would it know there is a leaky injector and keep running?

Thanks again for the help!

 

[Chuck Leeper]

Chuck, you cleaned and balanced these injectors YEARS ago for me. I appreciate all your help!

Please help me understand your statement below:

Bottom line: Unless the fuel pump is continuing to run after the prime cycle, the "leaky inj" theory is not valid.

I thought the fuel pump primes for two seconds and then shuts off, regardless. How would it know there is a leaky injector and keep running?

Thanks again for the help! [/QUOTE]

It wouldn't. There is only a timed event in the prime cycle.
As I see it:
1. You said that as long as the key is on, the noise continues, until you pull the inj fuse. Then, the noise stops.
The prime cycle is long over once you do that.
If the inj is stuck open, the psi drop is not going to turn the pump back on.
If the inj is shorted open, then it would continue to allow fuel to leak, until it runs out of pressure, or you cut the power to it.
What have you found w/ the plugs? NE of them doused in gas?
I'd have to look at the shop manual to see what else is/may be tied into that fuse.

 

[Raeban]

Here is the shop manual diagram for that fuse. Not a lot on it. Something to consider is that if he changed the battery cable he messed with the fusible links at the starter. One goes to the blower motor for the high setting but as mentioned above that should be easy enough to hear and diagnose.

 

[John Larkin]

You can unplug the fuel pump behind the rear bumper and then put the fuse back in.