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88 mustang GT conv

  • Thread starter Thread starter billl
  • Start date Start date Nov 24, 2018
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jrichker

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Dec 17, 2018
#21
  • Dec 17, 2018
  • #21
Check fuel pressure:
The local auto parts store may rent or loan a fuel pressure test gauge if you don't have one.
Disconnect the vacuum line from the fuel pressure regulator. Check it for evidence of fuel present in the line by removing it and blowing air through it. If you find fuel, the fuel pressure regulator has failed. Reinstall the line; leave the fuel pressure regulator end of the vacuum line disconnected. Then cap or plug the open end of the vacuum line and stow it out of the way.
Connect the fuel pressure test gauge to the Schrader port located just behind the alternator.
Turn the ignition switch on & start the engine. Observe the pressure: you should see 38-41 PSI at idle.
Turn the ignition off; reconnect the vacuum line to the fuel pressure regulator. Then disconnect the fuel pressure test gauge. Watch out for squirting gas when you do this.

Fuel pump pressure test
Disconnect the larger of the two fuel lines up by the Schrader valve. It is the return line and does not have the Schrader valve on it. Find a piece of rubber fuel hose and clamp it on the return line coming from the regulator. Stick a bolt in the other end of the hose and make sure that all your connections are tight and leak proof as possible. When this powers up, you don't want fuel squirting everywhere. Hook up the fuel pressure test gauge. Turn the ignition switch on and watch for leaks. You may want to use a helper inside the car to cut the switch off quickly if you have a leak. To trick the fuel pump into running, find the ECC test connector and jump the connector in the Upper RH corner to ground.



Caution!!! You have blocked the return line for the fuel pump! Pressure will rise very quickly past safe levels with a good pump
If the pressure goes up past 55 PSI, the pump is good and the fuel pressure regulator is bad. If the fuel pressure does not hit 55 PSI or more in a few seconds, the pump is bad or you have electrical problems.
 
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billl

New Member
Nov 24, 2018
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las vegas
Dec 17, 2018
#22
  • Dec 17, 2018
  • #22
jrichker said:
Check fuel pressure:
The local auto parts store may rent or loan a fuel pressure test gauge if you don't have one.
Disconnect the vacuum line from the fuel pressure regulator. Check it for evidence of fuel present in the line by removing it and blowing air through it. If you find fuel, the fuel pressure regulator has failed. Reinstall the line; leave the fuel pressure regulator end of the vacuum line disconnected. Then cap or plug the open end of the vacuum line and stow it out of the way.
Connect the fuel pressure test gauge to the Schrader port located just behind the alternator.
Turn the ignition switch on & start the engine. Observe the pressure: you should see 38-41 PSI at idle.
Turn the ignition off; reconnect the vacuum line to the fuel pressure regulator. Then disconnect the fuel pressure test gauge. Watch out for squirting gas when you do this.

Fuel pump pressure test
Disconnect the larger of the two fuel lines up by the Schrader valve. It is the return line and does not have the Schrader valve on it. Find a piece of rubber fuel hose and clamp it on the return line coming from the regulator. Stick a bolt in the other end of the hose and make sure that all your connections are tight and leak proof as possible. When this powers up, you don't want fuel squirting everywhere. Hook up the fuel pressure test gauge. Turn the ignition switch on and watch for leaks. You may want to use a helper inside the car to cut the switch off quickly if you have a leak. To trick the fuel pump into running, find the ECC test connector and jump the connector in the Upper RH corner to ground.



Caution!!! You have blocked the return line for the fuel pump! Pressure will rise very quickly past safe levels with a good pump
If the pressure goes up past 55 PSI, the pump is good and the fuel pressure regulator is bad. If the fuel pressure does not hit 55 PSI or more in a few seconds, the pump is bad or you have electrical problems.
Click to expand...
Great I will work on this tomorrow! pulled vac, hose off reg no gas present note also spraying carb cleaner into intake will start eng. till it starts to idle then idles just cant give it gas load without it backfiring through plenum





]
 
Last edited: Dec 17, 2018
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billl

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Nov 24, 2018
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las vegas
Dec 17, 2018
#23
  • Dec 17, 2018
  • #23
Just spitballing now but starting to think clogged fuel line? clogged pump? need to plug reg hose and check return line tomorrow
 
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billl

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Nov 24, 2018
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las vegas
Dec 18, 2018
#24
  • Dec 18, 2018
  • #24
OK checked codes today with no work on car yet except banged on TAD, changed to 41 R , 91 R back to sensors. Actually fuel gauge shows 0 psi but still have to buy hose to plug req. My question is do any of the codes I get have to do with my problem of spray cleaner to start eng. then burps through intake when load in applied. the codes are HO2S lean is it lean because fuel flow is bad or visa versa?
 
Last edited: Dec 18, 2018

General karthief

wonder how much it would cost to ship you a pair
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Dec 18, 2018
#25
  • Dec 18, 2018
  • #25
You need to address the zero fuel pressure issue
 
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billl

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Nov 24, 2018
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las vegas
Dec 18, 2018
#26
  • Dec 18, 2018
  • #26
General karthief said:
You need to address the zero fuel pressure issue
Click to expand...
True hopefully will work it more tomorrow
 
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billl

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Nov 24, 2018
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las vegas
Dec 19, 2018
#27
  • Dec 19, 2018
  • #27
Buying new shrader valve for fuel rail tomorrow
 
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billl

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Nov 24, 2018
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las vegas
Dec 23, 2018
#28
  • Dec 23, 2018
  • #28
changed valve... OEM test kit from autozone 2 borrowed had cut o-ring in FORD adapter when I got them... Got a third kit from another autozone brand new hand tightened adapter leaked.. 1/4 turn with wrench leaked 1/.2 turn with wrench leaked tightened more and it just got loose again took it off o-ring cut .. a customer in the store said he had the same problem.. anybody else had this problem with OEM test adapter for FORD from autozone?
 
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billl

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Nov 24, 2018
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las vegas
Dec 27, 2018
#29
  • Dec 27, 2018
  • #29
Finally got good o-ring from orielly hand tight 12psi with reg. plugged
 
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billl

New Member
Nov 24, 2018
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las vegas
Jan 3, 2019
#30
  • Jan 3, 2019
  • #30
is there any device in tank to stop me from siphoning gas with a hose out of tank to drop tank 88 gt conv. mustang
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
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polk county florida
Jan 3, 2019
#31
  • Jan 3, 2019
  • #31
At the end of the fill tube there is a piece of metal that is angled so you would have to use a tiny hose and it would take forever to siphon gas out through the filler neck. Does your pump not run?
 
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billl

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Nov 24, 2018
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las vegas
Jan 3, 2019
#32
  • Jan 3, 2019
  • #32
pump runs just looking at optional way and just wondering
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,570
203
polk county florida
Jan 4, 2019
#33
  • Jan 4, 2019
  • #33
You can disconnect the fuel line, clamp a hose to the end coming from the tank, put the other end in a can, bucket or your significant other's car, truck or motorcycle and jump the pump at the test port.
 
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billl

New Member
Nov 24, 2018
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las vegas
Jan 4, 2019
#34
  • Jan 4, 2019
  • #34
plan A
 
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billl

New Member
Nov 24, 2018
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las vegas
Jan 11, 2019
#35
  • Jan 11, 2019
  • #35
Turned out to be a split fuel hose at the fuel pump
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,570
203
polk county florida
Jan 12, 2019
#36
  • Jan 12, 2019
  • #36
Glad to hear, alls good now?
 
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billl

New Member
Nov 24, 2018
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las vegas
Jan 19, 2019
#37
  • Jan 19, 2019
  • #37
Runs strong and got smog check.
 
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