1quickTransAm

iTrader: (4)

I was going to spray for the first time tonight, but I am having a hard time setting my fuel pressure safety switch. I tried setting it by these instructions from Chris at Nitrous Outlet (below), but it's not acting consistently. The solenoid will click at one set point, then I'll click the micro switch again and it will spray fine and I can turn the setscrew two or three times and it still keeps spraying. What am I doing wrong? Any tips? I really wanted to spray tonight.

Instructions I'm following;

*If you need the FPSS adjusted i'd suggest you take the nozzle or plate and out it in a bucket. There is a rubber nipple on the top of the FPSS that you will need to remove to reveal a set screw. Now you will need to activate the system and as the fuel is flowing out of the nozzle into a bucket you will need to turn the screw clockwise ( to increse the set PSI ). Only do it in short 5-8sec bursts so that way you're not heating the noids up for no reason. As you are turning the set screw once the fuel starts to sputter out of the nozzle then you will need to stop turning the screw and now turn it about 3/4 to a full turn counterclockwise and that should have the FPSS set to the flowing fuel pressure.

Burrhos

iTrader: (3)

Where is your FPSS located?

Mine is teed into the fuel feed to the rail.

I just used a test light to check which side had constant ground and which had intermittent ground when the switch was thrown. Once I figured out which side was constant ground, I put the test light on the opposite side and turned the **** until the light came on, indicating that the switch was seeing pressure and completing the circuit when the car is running.

I turned the car off and checked the same pin and sure enough, it had no ground. I had my wife start the car while I held the test light in place and as soon as the car fired up, the test light came on so I was/am convinced it was set appropriately.

Here is how my fpss is setup.

1quickTransAm

iTrader: (4)

Mine is located just before the fuel solenoid.

Using a test light seems like a good idea. The thing that concerns me though is that I was doing it based on observing actual solenoid action and fuel flow, which should obviously be accurate, but it seemed all over the place...

Not what I was expecting.

Burrhos

iTrader: (3)

How old is the fuel noid?

1quickTransAm

iTrader: (4)

Not sure... bought the basic kit (bottle, lines, solenoids, purge, FPSS) used from someone on this forum. All the rest I bought new. I did disassemble the solenoids to inspect and tested functionality, but not sure how old they are.

Burrhos

iTrader: (3)

If the fuel isn't flowing steadily out of the fuel noid then your FP is off or there is a restriction in the noid.

1quickTransAm

iTrader: (4)

It does flow steadily at some FPSS settings, but clicks on/off rapidly at others. I expected this from the "how to" write-up, but it is the inconsistencies that concern me. It will click on/off at one setting, then I'll close the microswitch again at the same setting and it will flow fine so I'll turn the set screw two or three times and it still is flowing.

I'm not sure why the cut-off point isn't more consistent...

Burrhos

iTrader: (3)

Oh, I misread what you were saying. The fuel is consistent but the point at which the microswitch activates/deactivates is not. I understand. Is the switch new? Perhaps it's on the fritz?

1quickTransAm

iTrader: (4)

^ Exactly!

No, its used so I really don't know its history. I got it used with the solenoids and bottle but it all looked almost new (even when taking apart the solenoids). Pretty much everything else is new.

Burrhos

iTrader: (3)

I'd buy a new one. They're cheap enough and important enough to warrant the necessity in its functioning correctly.