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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Fuel Noise from the rear after shutting off car

  • Thread starter Thread starter Redfire Fox
  • Start date Start date Jun 19, 2020

Redfire Fox

Active Member
Dec 29, 2011
56
26
39
Jun 19, 2020
#1
  • Jun 19, 2020
  • #1
After driving my 1991 fox around town and parking it I shut the car off. I then hear this whiny moan coming from the rear. Is this the fuel pump making the noise? What else could it be?
Also if I let my car sit for two days or more it takes a about 6-7 seconds of cranking before it starts. If I let my car sit for a day or less it takes about 2-3 seconds before it starts. Is my fuel pump going bad? Its a ford 190 lph. It has about 30k miles on it.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Jun 19, 2020
#2
  • Jun 19, 2020
  • #2
Well let me ask:
have you checked fuel pressure?
is the purge canister connected and functional?
can you hear the fuel pump prime?
 

Redfire Fox

Active Member
Dec 29, 2011
56
26
39
Jun 19, 2020
#3
  • Jun 19, 2020
  • #3
Fuel pressure is 38-39psi with vacuum off with car running.
Not sure about the canister being functional but it is connected
Yes I hear it the pump prime before I start it and its quiet when car is running
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,951
10,589
203
polk county florida
Jun 19, 2020
#4
  • Jun 19, 2020
  • #4
Ok, here is what I would do: with the car running, go back to the fuel filler and take the cap off, turn the car off to see if the moan happens. If it does not moan that may indicate it is not venting properly.
 

Redfire Fox

Active Member
Dec 29, 2011
56
26
39
Jun 20, 2020
#5
  • Jun 20, 2020
  • #5
It stopped making the noise after doing what you told me. So how do I fix this? Replace the purge valve? The one I got on now is 30 years old.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,951
10,589
203
polk county florida
Jun 20, 2020
#6
  • Jun 20, 2020
  • #6
Well the next thing I would do is, with the engine running, and the gas cap on, find and disconnect the vacuum line the runs from the fuel tank to the purge canister and turn off the engine, listen for the wheezing
 

Redfire Fox

Active Member
Dec 29, 2011
56
26
39
Jul 8, 2020
#7
  • Jul 8, 2020
  • #7
Well fixed my rear moaning noise during ignition on engine off I been getting. Also no more long cranking issues when cold and engine stalls during hot starts and no more fuel pressure going to zero after shutting the car off. Yup you guessed it, I changed my fuel pressure regulator diaphragm in the Kirban. I also noticed my car runs much smoother when I accelerate.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Jul 8, 2020
#8
  • Jul 8, 2020
  • #8
To fix a whiny moan in the back, I would have checked on who was tied up in the trunk, or who I forgot in the back seat .
You guys are smart to have nailed it with the first response.
 
Reactions: General karthief
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