1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

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Old Jan 15, 2011 | 12:12 PM
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780rx7's Avatar
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there are no stupid questions....

Well, except maybe this one. So, my son's car died (again). Had it towed (again). You may recall that we had a ground problem a while back to the rear of the car so that the fuel pump would not work when the brake lights or rear defog etc. were on. Turned out to be a bad ground. this was fixed and remains strong. during all of this testing, I became very familiar with the sound of the fuel pump when it was running before starting the vehicle. It was a fast clicking sound. Anyways, when it died again this time, I again couldn't hear the fuel pump and immediately thought it might still be a gounding issue, but I checked it and like I said, it reamains strong. Now there is no clicking sound. the power to the pump is good all the way (tested all the way there). you can hear an electrical hum, but no clicking/pumping sound. so, I'm guessing the fuel pump is shot now? My question is, what kind of a sound should it make? Is the clicking sound normal or abnormal? Right now the hum is almost inaudible. The car won't start and acts like there is no fuel. When it died, it just died like it ran out of gas.

I'm planning on replacing the pump, but any comments?

Thanks guys

Neil & Liam
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Old Jan 15, 2011 | 12:21 PM
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the constant shorting of that ground could have weakened the pump and it is just now dying sounds about right to me
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Old Jan 15, 2011 | 12:21 PM
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if the pump is humming, disconnect the line to carb and see it gas shoots out. If doesnt, weak and such, check for blockage before the pump (ie, filter). Otherwise, replace it.
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Old Jan 15, 2011 | 06:44 PM
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Originally Posted by WackyRicer
if the pump is humming, disconnect the line to carb and see it gas shoots out. If doesnt, weak and such, check for blockage before the pump (ie, filter). Otherwise, replace it.
+1. Make sure fuel's getting into it (filter & pickup are clear). If voltage is good but fuel's not coming out at required pressure and flow rate, pumps' the answer.
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Old Jan 16, 2011 | 12:35 AM
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i use a ball bearing stick it in the end of the feeding tube and the pump should shoot it out, not like really fast but if its a strong pump it should pop it out rather quick. just be sure not to jam it in just so its about 50% in the hose.
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Old Jan 16, 2011 | 11:15 AM
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Another great idea....
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Old Jan 16, 2011 | 10:34 PM
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TX Dude!!!

What a great idea for a sweet disaster! Now all you need to go with the ball bearing is a lighter! Flaming ball bearings shooting across the garage FTW!

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Old Jan 16, 2011 | 11:07 PM
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Originally Posted by DallasFC1
What a great idea for a sweet disaster! Now all you need to go with the ball bearing is a lighter! Flaming ball bearings shooting across the garage FTW!
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Old Jan 17, 2011 | 12:56 AM
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well your not supposed to look at it or point it a window....lol
yes its risky but it works to see if its buiding pressure.
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Old Jan 17, 2011 | 06:46 AM
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lol, ball bearing FTW!
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Old Jan 17, 2011 | 04:30 PM
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From: Chino Hills, CA
Originally Posted by Man_in_black49464
well your not supposed to look at it or point it a window....lol
yes its risky but it works to see if its buiding pressure.
So does a fuel pressure gauge.

I know; radical thinking.
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Old Jan 18, 2011 | 10:27 PM
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It was definitely a bad pump. Installed the new one tonight and fired it right up.

Thanks for the feedback. Hopefully next time I post it won't be after I had it towed home (again).

Cheers,

Neil & Liam.
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