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Replaced Fuel Pump and Regulator...Survey Says, Still does the same damn thing

  • Thread starter Thread starter 1988WHTGT
  • Start date Start date Sep 8, 2005

1988WHTGT

Member
Mar 31, 2005
270
0
17
Guyton, GA
Sep 8, 2005
#1
  • Sep 8, 2005
  • #1
So i posted a while back about my car stuttering and acting weird. Finally ckecked the fuel pressure and it would drop when increasing revs. So I put in a Walbro 255 and a Kirban AFPR, set my prsssure at idle at about 43 psi with the vaccum hose off....rev it up and pressure still drops.....whats going on? Bad injector somewhere? Put a new sock on the pump and new filter when I did everything.
 

txstang84

15 Year Member
May 21, 2005
1,639
42
69
Tuscola, tx
Sep 8, 2005
#2
  • Sep 8, 2005
  • #2
kinked line anywhere?
 
P

Polter83

New Member
Jul 27, 2004
74
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0
Sep 8, 2005
#3
  • Sep 8, 2005
  • #3
Where is the gauge inserted.. on the regulator or on the line near alternator?
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Sep 8, 2005
#4
  • Sep 8, 2005
  • #4
txstang84 said:
kinked line anywhere?
Click to expand...

I would think a visual check of all lines from the tank to the fuel rails would help. If that's the problem it should be obvious by looking at the line.

Can't think of any other potential causes right now.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Sep 8, 2005
#5
  • Sep 8, 2005
  • #5
Does it dip for a second and return or dip and stay low?
 

5.02GO

Founding Member
Jun 26, 2001
308
0
16
Ky, Blue Sky Country
Sep 9, 2005
#6
  • Sep 9, 2005
  • #6
Fuel pump is in backwards!



btt..........
 

1988WHTGT

Member
Mar 31, 2005
270
0
17
Guyton, GA
Sep 9, 2005
#7
  • Sep 9, 2005
  • #7
The gauge was inserted on the line and it dips when I rev it but then goes back to around 43 at idle. Haven't checked the lines for any kinks yet
 
S

ss93cobra

Founding Member
Apr 10, 2002
1,422
1
0
Wilmington NC
Sep 9, 2005
#8
  • Sep 9, 2005
  • #8
Checked the filter?
 

Look Its Aaron

Your car looks like it came straight from Mexico.
Founding Member
Nov 18, 2001
2,634
0
48
Fontana, Cali
Sep 9, 2005
#9
  • Sep 9, 2005
  • #9
Check to make sure the filter is flowing correctly?
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Sep 9, 2005
#10
  • Sep 9, 2005
  • #10
I just had an odd thought.

What is your engine vac like?
How is your vac to the regulator routed?
If it is spliced from the crankcase/pcv then blowby pressure could be affecting how fuel pressure changes?

just a thought.
 
B

bsedwebt70-5.0

New Member
Jul 1, 2004
320
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Charlottesville, VA
Sep 9, 2005
#11
  • Sep 9, 2005
  • #11
just a thought - are you checking the fuel pressure with the vacuum line off and then tapping the gas for it to drop? or do you have the vacuum on and it drops when you tap the gas? It is supposed to go up a bit when you tap the gas with the vacuum line on and I believe it may drop a bit if you tap the gas with the vacuum line off because it is already at the max fuel pressure and you just caused the injectors to "steal" some of the pressure for a moment -- just a thought!
 

1988WHTGT

Member
Mar 31, 2005
270
0
17
Guyton, GA
Sep 11, 2005
#12
  • Sep 11, 2005
  • #12
Put a new filter in....and it was doing it with the vac line on and off.....I just dunno....i did notice that the top of one of injectors is a little wet.....u think it could not be getting enough gas on that cylinder and making it break up a little?
 
J

JB66

New Member
Aug 21, 2004
565
1
0
New York
Sep 11, 2005
#13
  • Sep 11, 2005
  • #13
Make sure your fuel return line is flowing. Has this always been happening since you had the car or did it start after you changed something?
 

1988WHTGT

Member
Mar 31, 2005
270
0
17
Guyton, GA
Sep 12, 2005
#14
  • Sep 12, 2005
  • #14
It just started randomly....it was fine after the rebuild and then one day it just started doing it.
 
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