1977 911s Won't Start Problem - Help!

[MattW]

My 911 was running better than ever when I put it into storage late last fall & this spring she doesn't want to start.

It turns over fine and it does have spark, so I'm pretty sure its a fuel related problem. Something that concerns me is that I don't hear the whine of the fuel pump when the ignission switch is on. Also with the ignition switch on and the air filter off, when I lift up on the switch in the airbox, I hear a "click", but never do hear any spraying sound.

There was some evidence of being visited by mice, but I've checked all the wires around the fusebox & they look ok. All the fuses check out to, as does the red relay.

Can anyone tell me what I should look for next?

Thanks very much!

-Matt

[makaio]

Do you have fuel in the tank? Have you swapped out the fuel pump relay with a known good one ( first thing I would try if you have fuel in the tank).

[Targa Dude]

Matt, Evidence of mice?? you need to elaborate a little.. what exactly do you mean by evidence? My buddies 72T had evidence of mice and the evidence was, those little bass-turds chewed trough his main harnesss that is routed along the rear cross member behind the enigine. They chewed thru 15 or so wires that are in the bundle of thirty or so Wires.

Now You might wanna invest in a V/Ohm meter and start buzzing out some critical wires and cabling.

Edit: Where you located?

Jorge (Targa Dude)

[MattW]

Hi Matt. Yep, got fuel in the tank. No, I haven't swapped the fuel pump relay. This is the red knob deal at the top of the fusebox, right?

[MattW]

Hi Jorge, Yeah, really big mice - Rats even. Mostly the evidence was brown and sounded like a bell (dung!) and empty poison wrappers. They chewed a few holes through the felt trunk liner, but I've looked over all the wires & it really doesn't appear like (at least in the trunk) that they bothered anything else. I didn't see any evidence of the critters within the engine compartment, but just in case, what's the best way to take a look at the main harness?

Can you tell me where is the fuel pump located? My Hayes manual show's a great picture of it and explanation of how it works, but it fails to mention where it is. Would it make sense to first check to see if there's current getting to the pump?

Thanks!

-Matt

[makaio]

The fuel pump is directly behind the fuel tank, under the car.

Yes, your fuel pump relay should be red. What you can do is pull the horn relay, insert the fuel pump relay in its place, and see if the horn works. If it does, your relay is good. If it doesn't, then your relay is bad.

[Targa Dude]

Matt, the fuel pump is located underneath the front of the car, you have to jack the car up and remove the skid plate it's tucked up in there. Have you checked your fuel pump relay? When you turn the ignition key to the on position can you hear the CDI Box in the engine compartment whine?

Jorge (Targa Dude)

[MattW]

Hi Matt,

>>insert the fuel pump relay in its place, and see if the horn works
Cool trick, I'll give that a shot before I go after the fuel pump.

Thanks!

-Matt

[MattW]

Thanks Jorge! I guessed it was underneath and near the tank, but a quick look under the card didn't help me. I'll take a look at the relay first. When I turn the key to the on position, I'm not hearing the CDI box do anything. When I lift the switch in the airbox, I do hear a click coming from the front of the car and then a more quiet click from the engine compartment - I wasn't able to identify where the click came from in the engine compartment.

I'll take a look & let you know what I find.

-Matt

[MattW]

Ok, the horn works. With the fuel pump relay in place of the horn relay, the horn still works. So, I guess the fuel pump relay is ok. I inspected all of the wires again in the trunk area & can't see any signs of chew-throughs.

I re-checked, and with the ignition key on I don't hear the CDI box making any noise. The slight clicking sound that I hear from the engine compartment when I trip the lever in the airbox seems to be coming from behind the engine - like in the bumber, where the taillights are. Does that make any sense?

Still stumped...

-Matt

[MattW]

Hey! I found the problem!! There's a small hole, say a little larger than a silver dollar, under the skid plate, right next to the fuel pump. Just the right size for vermin. But, apparently the wire leads supplying power to the fuel pump was making entry a little difficult for the bigger vermin - so they chewed through it. Voilla! better doorway.

Life's better now that I know what the problems is - lkooks like it'll be pretty easy to fix.

Many, many thanks to Matt and Jorge for helping me troubleshoot this! I wouldn't have been able to do it without you guys.

Thanks.

-Matt

[MattW]

Hey, I just realized I never mentioned where I'm from. Near LaCrosse, Wisconsin.

-Matt

[makaio]

Glad you found your problem.

And it sounds like you need a car capsule to store your car in, so the mice can't get in there.