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Kirbin adjustable fuel pressure question...please help!

  • Thread starter Thread starter Ostang351
  • Start date Start date May 25, 2004
O

Ostang351

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Feb 16, 2004
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May 25, 2004
#1
  • May 25, 2004
  • #1
I bought the car used and I am almost positive it has a kirbin on it. From the looks of it on the car and what pictures of the kirbin look like online, it is a match. Anyway, I read that a feature of the kirbin is that you don't need to remove the vaccuum line to read the pressure. (I have a gauge where the schrader valve was). It reads close to 40 with the vac line on, but if I take it off, it is around 45 or higher. Can anyone confirm this that I can leave the vac line on to read the gauge at idle. When I rev it, the gauge goes to about 36psi. In the morning the car doesn't want to idle and will pop out the intake a few times then clean up. Adjusting the FP hopefully will fix it. (I hope). Thanks in advance.
 

ECU5.0

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Jan 10, 2004
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May 25, 2004
#2
  • May 25, 2004
  • #2
take the vacuum line off but plug it with your finger and set the pressure at like 32 and than put the line back on and see how it runs. what are your other mods? that really determines what pressure you should be running
 
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Ostang351

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May 25, 2004
#3
  • May 25, 2004
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Thanks for the reply. I have Edlbrock alum. heads, B303, 1.72's, Cobra upper and lower, Mass air, Throttle body, Cold air intake, BBK unequal length, Basani high flow cat pipe, flowmasters, 3.73's, stock bottom end. I am about to drive it now at 41 with the vac on then I will try your way to see what the difference is....
 

ECU5.0

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#4
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yeah...try setting it at 32-33 with vac off and than put the vac back on and see how it does
 
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PRO50SC

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Dec 28, 2003
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May 25, 2004
#5
  • May 25, 2004
  • #5
Ostang351 said:
I bought the car used and I am almost positive it has a kirbin on it. From the looks of it on the car and what pictures of the kirbin look like online, it is a match. Anyway, I read that a feature of the kirbin is that you don't need to remove the vaccuum line to read the pressure. (I have a gauge where the schrader valve was). It reads close to 40 with the vac line on, but if I take it off, it is around 45 or higher. Can anyone confirm this that I can leave the vac line on to read the gauge at idle. When I rev it, the gauge goes to about 36psi. In the morning the car doesn't want to idle and will pop out the intake a few times then clean up. Adjusting the FP hopefully will fix it. (I hope). Thanks in advance.
Click to expand...
Is the only time you have a problem with it in the morning when it is cold? If so, could be an IAC problem and not f/p. Could also be your f/p is bleeding down over night and starving the motor when cold. Need a little more description of the problem. How does it run otherwise?
 
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Ostang351

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  • May 25, 2004
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Yes, it only does it when it is cold. It used to start just fine when cold and threw the warm up cycle, it never wanted to die. Then would I would start to drive, I would shift easy from 1st to 2nd and the motor would hesitate then pop a few times. With more gas it would clean up and not do it anymore. The Mass Air, 02's, cap, rotor, plugs, wires are all new. Now it doesn't want to idle when it is cold. I warm it up so it idles and then drive and if I shift fast enough, still accelerating easy, it won't pop. I am stumpted. Also, is it true what I wrote earlier about the Kirbin, not having to take of the vac to test? I hear that everyone sets around 40 with the vac off. When the car warms it runs fine. I pulls hard after 3000 but I think that is the cam (B303). Thanks for the posts so far.
 

jrichker

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May 26, 2004
#7
  • May 26, 2004
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Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html
 
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Ostang351

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I pulled the codes and I get a 31 (EVP out of range) and 63 (TPS). The TPS is showing .98 and I have no idea what the EVP is.
 

jrichker

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CODE: 31 (KOEO) - EVP circuit below minimum voltage. Vref (5 volt reference voltage supplied by the computer) missing or broken wire or bad connection in circuit. Use a DVM to check for 5 volts on the orange/white wire. If it is missing, look for +5 volts at the orange/white wire on the TPS or MAP sensor located on the firewall near the center of the car. With the sensor removed from the EGR and still connected, press the plunger and watch the voltage change on the brown/lt green wire. Check for the same results on pin 27 on the computer.

Code 63 - Throttle Position Sensor (TPS) signal too low TPS. Vref missing (5 volt reference voltage supplied by the computer), bad connections or damaged wiring, TPS sensor failed, TPS sensor way out of adjustment. Use a DVM to check for 5 volts on the Orange wire. If it is missing, look for +5 volts at the Orange wire on the EGR or MAP sensor located on the firewall near the center of the car.

The common point for EGR & TPS is the VREF voltage. make sure you have the +5 volts as detailed above.
 
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