Tom

I've got a stock 12A, stock nikki, weber fuel pump and Holley FPR.

Left the office tonight, car starts great. Idles perfect. Drive 2 or 3 miles down the freeway, stop at a light off the exit and my car is sputtering like crap, losing idle. I've got to keep it throttled to stay alive. I get to a parking lot, look under the hood while the engine barely idles. I notice I have very little fuel pressure according to my gauge (less than 1psi). However- I have a clear fuel filter in line after the FPR and there is a PLENTY of fuel coming through...

So I try to up the pressure with the adjustment screw (which was previously locked at like 3.5psi). I manage to get it to 3psi. The car is still running rough. I take off the air cleaner and look into the carb. The primaries looked normal but the secondaries are LOADED with fuel above the butterfly valves. I mean completely loaded to the top.. So I tap on the carb a few times and throttle it hard like it's flooded. After the cloud of smoke cleared, the secondaries looked normal and the idle returned to normal (but still a little rough).. I drive home ok. The secondaries seem to open just fine.

I get home and try to play with the fuel pressure a little bit but can't get it any farther past 3psi. The weber pump claims 6psi (from the pump) and has maybe 1000 miles on it.

Now- I have absolutely NO clue what happened. I'd like to figure out what happened with the carb and why the fuel pressure will not rise above 3psi (when I could previously raise it past 4.5psi with no problems).

Anybody got any clues???

cdrad51

The EXACT same thing happenned to me the other day, early in the morning, and it's funny how I inspected the carb and found the same thing, a puddle in the secondaries. And did the same thing to clear it up, with the same results.The only thing I can figure out is that the night before I was testing the FPR for leaks several times and so had the key on the "on" position, but without starting the engine, and so I assumed that the cummulative time of all the test flooded the carb.

rototiller1

your problem is in the fuel tank (DIRT) , drain the tank, flush it out, change the filter

zgate

I had the same problem, but I had less then 100 miles on a new pump and FPR. It turned out to be a bad FPR - Test yours.

REVHED

The flooding was probably caused by wear or debris in the needle and seat. It's hard to see how that could be related to a lack of fuel pressure. Maybe the guage malfunctioned?

Doubleohsmurf

Check your vacuum connection to the idle control solenoid on the vacuum relay, if thats off it could be the prob...other than that its either your carb or the fuel, im pretty sure.

Tom

Nope. Got a clean stock fuel filter AND one installed after the FPR.. Lines are as clean as a whistle.

I'll check the vac hook-up. If it is a faulty FPR, I will officially give up on Holley's. My first Holley FPR went wacko after a few months.. But, I am getting steady flow now (albeit 3psi)...The gauge is new and in good working order too...

cdrad51- this is getting weird. It seems your issues and my issues are running parallel to one another..

cdrad51

Yeah no kidding - make sure you check your turning signal and hazards lights!

Sterling

Tom where are you measuring the pressure from?
Sounds like you may have perfed something in the regulator, and you're actually running much higher pressure that you thought.
In other words, the fuel pressure regulator aint regulating.

Tom

The gauge is mounted on one of the outlet ports on the Holley fpr.
The FPR is working- If I dial down the pressure it is certainly noticeable. It just stops dead at 3psi, no higher. If i throttle the motor and hold it at like 5500 rpm, I can see the pressure drop (according the gauge) to like 2.5 psi..

If the FPR had a temporary seizure, like not regulating- would it cause a massive flooding of the secondaries and not the primaries?

xrotaryguy

I think that the notion that the fload needle had a little dirt in it is a good explination of why the secondaries flooded. I've had a lot of these carbs do that from time to time. I also think that if you had a little dirt in the secondaries then its possible that there is also a little piece of grit in the regulator as well. good luck

trochoid

iTrader: (6)

I just put a Holley fpr on my 12a. My mikuni just wasn't running right and I wanted to check fuel pressure. With the fpr and gauge I could only get 3 psi at idle and it dropped from there with any increase in rpms. Changed to a carter fuel pump that I had laying around and all is good. Set the fpr at 4.5 psi and it runs fine too nearly 8k. You also might want to check your fuel pickup in the tank. The in tank filter may be partially plugged. I also had another 12a that would idle fine but when you gave it any pedal, the fuel bowls emptied and the car died. Turned out the pickup filter was split and the pickup tube was almost completely blocked. Just enough of a hole for idle.

Tom

I started the car tonight and let it run for about 15 minutes. I'm reading over 4.5psi now, and I have not touched the fpr since last I posted. Car is running fine as well. No flooding in the secondaries.
I dunno- maybe these holley fpr's just have it out for me...

I'm going to keep an eye on the fuel filters and see if there is something coming through the lines. Thanks for everyones input.

pillage6

Check the electrical connections on the fuel pump.