Ok, so first off, I was wondering if I need to adjust my fuel pressure after installing a Walboro 255. I'd assume the regulator still does it's thing by regulating the return but maybe not. So maybe that's my main problem but...
I always wondered why I saw so many threads around the net saying "new fuel pump, now I have problems." I figure it's pretty straight forward; pull the old, install the new with the sock properly aligned and the wiring properly connected. But I put mine in and suddenly, starting problems! This car used to ALWAYS fire almost the instant I hit the key, literally. Now? Sometimes it fires after a moment of turning over (like you'd hear on the average car) but more often takes a few seconds (and yes, this is long, count it once!). Sometimes it even requires that I let off the key and turn it over a second time, which results in an immediate start up every time. The car also surges every now and then (600 -1000 rpm at 'idle') and overall feels different, but much of this may be in my head. Thoughts?
As far as not starting right away, this makes me think that the line isn't getting up to pressure with the initial second or so that the pump cycles when you first turn the key to the on position. Turning the key on a second time cycles the pump again and now you have enough pressure to properly fire the injectors. Not sure why it would do this - bad check valve?
where is there a check valve? If it's not on the pump it seems unlikely... the chance of it popping up the same time I changed the pump is pretty small..?
I thought there was one in the pump. I assume it's highly unlikely that the little hookup hose is leaking.
yeah, i inspected the hose, clamped it real good... as for the check valve, idk... it does make sense. I guess I'll have to buy another pressure gauge (mine went missing) and do some testing during fuel pump priming.
Yes, watching the pressure on a gauge will really help.
If you're running a stock regulator then that is part of your problem.
The diaphram on the stocker won't hold back the amount of gas pushed out by a 255 LPH pump when the car is at idle. Pressure will actually creep up causing a rich condition at idle. Leave it in park for 5 minutes and smell for yourself.....if it stays running that long.
I was wondering about the 255 and fuel pressure at idle, but I've only used a 190 lph with one (& it worked fine) so I couldn't be certain enough to comment. You can also check pressure at idle after you check the pressure prior to startup (after turnng the key on.)
I had an adjustable regulator before the 255 pump.....I've heard plenty of horror stories about the stock regulator and the big pump. Seen a couple first hand.
I have a Mallory adjustable FPR...