racetronix pump low psi
Thread Starter
On The Tree
Joined: Jan 2008
Posts: 145
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Here the video of my fuel pressure guage at idle then stalled, lemme know if you can give any insight to my problem. Video starts with the engine running and I rev it a few times to show how easily the pressure is dropping. THen I stall it on purpose, then towards the end start it back up.
http://www.youtube.com/watch?v=rXhu_gjxkwE
thanks
Justin
http://www.youtube.com/watch?v=rXhu_gjxkwE
thanks
Justin
That video is interesting...my fuel pressure always takes several minutes after killing the car to drop that low. I'm not familiar with boosted application but seems to me that is abnormal. Btw i also have the full racetronix kit (pump/harness) but I test mine manually at the rail, so idk. Sorry i know im not much help. Good luck!
The fact that you do not immediately lose fuel pressure leads me to believe that the regulator is not bleeding off, nor is there likely to be an intank line leak.
The way the pressure drops when you tap the throttle, is familiar....
but your pressure is not that high to begin with. Typically you will have about 60-62 at idle & about 58 under load with a Racetronix pump.
Does the pressure drop severely under power?
Have you checked the pressure with another gauge? Yours would not be the first gauge that I have seen malfunction.
The way the pressure drops when you tap the throttle, is familiar....
but your pressure is not that high to begin with. Typically you will have about 60-62 at idle & about 58 under load with a Racetronix pump.
Does the pressure drop severely under power?
Have you checked the pressure with another gauge? Yours would not be the first gauge that I have seen malfunction.
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Verdad Gallardo Thread Starter
On The Tree
Joined: Jan 2008
Posts: 145
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k, i should be able to get another fuel pressure gauge of another guy, but it may be a few more days, until then I had one more question. My trip ometer resets to zero and my speedomoter goes up to the max then goes back to zero when i turn my car on if it sits for a day or two, or if I sat with my engine off and my lights on. I think this happens when ur battery goes dead. my thought is that possibly I have a weak battery or my alternator isn't putting out enough power to recharge the battery. Which might possibly mean that it's not giving enough power to my fuel pump?
Any thoughts or input is appreciated.
Justin
Any thoughts or input is appreciated.
Justin
I had the exact symptoms with my Racetronix install as you did, although mine is a 98. Didn't think it was my autometer electric fuel pressure guage, but after hooking up a mechanical guage to the fuel rail I got 64 psi at idle.
Now I need to determine if its the sender or the guage. As for the other problem I would get the battery tested.
Now I need to determine if its the sender or the guage. As for the other problem I would get the battery tested.
Thread Starter
On The Tree
Joined: Jan 2008
Posts: 145
Likes: 0
Thanx for the help, I took the car to top gear motorsports, and had him hook up a manual gauge right on the fuel rail, and sure enough the pressure was sittin at about 62 psi, so this whole time my problem was either my gauge or my sending unit. I think the reason it felt weak when i got on it ahwile back is because my spark plug wire had a small crack in it from the heat from the manifold. I got on it today and they broke right loose in 3rd 
Now I just need to determine if i need to replace the gauge or the sender unit.
Thanx for the help
Justin
Now I just need to determine if i need to replace the gauge or the sender unit. Thanx for the help
Justin
If its an autometer guage you can test the sending unit by measuring the voltage of the purple wire going into the back of the guage. If you have a 100 psi guage the voltage should be around 3 volts at 62 psi. Mine was only reading 2.6 volts which equals about 52 psi which is what the guage was showing. So now I need a new sending unit. You can get em on e-bay for about $94 shipped. Still expensive, but cheaper than buying a new guage!
