Prime shot issues
Installed Fitech 30012 last year with 95% success on my '69 Camaro rs/ss
Problem 1 (last year)
Last year was that after 2-3+ hours of driving rpm freezing at example 2400rpm only solution was to stop car waiting a few minutes, then car runs okay again for half to 1 hour again, the repeating....
I wasn't able to find problem, except from that i suspect internal linkage to bend because of heat or something like that ( I'm using 1/4inch fiber spacer) I tried to unconnect cable and carb wasn't able to shut completely and it feels like some kind of bending because I need to use little force to get it back to stop. but only 2-3 time a year I drive for 2+ hours so it hasn't been possible to locate/investigate further.
Problem 2
This year I mounted electric fan + collected all ground wires from battery terminal other ground places(fender lotations) to 1 isolated block placed hidden in fender to get a more clean look at battery terminals(did the same for battery +)
THEN
When I turn ignition on fuel pump last year it run for 5sec to get fuel pressure and Fitech unit fires 1-2 times(prime shot) to make starting quicker.
TODAY
1 time I turn ignition on pump runs for 10-20sec (controller adjusted to 5sec) and unit fires 6-19times BUT second time I turn ignition after example 10sec pump runs 5sec and unit fires once as last year where it worked fine.🤔🤔🤔🤔🤔🤔
I've watched that when unit fires "prime shot" rpm gauge needle jumps, could there be some kind of interference? I don't remember/noticed it did that last year.
Hope you at fitechefituning can help me because knowledge it's limited in my country.
Regards
Danish guy
Morten
I would say your current issue is a ground problem. I understand your desire to clean battery terminals up, but may need to try a different method. I tell everyone to ground this, that has never failed. 2ga battery to block, 10ga battery to frame, 10ga battery to body.
Your throttle issue is very curious...
Hi Austin
Thanks for your advices, after checking I discovered that car never had ground wire from battery to body, but only from battery to block and from frame to body.
But now car has 2ga from battery to block and same from battery to body and has what it looks OE flat wire/belt from body to frame BUT!!
Fitech unit now runs for 5sec and fire 1 "prime shot" as it did last year..
Another issue is that when pumps runs 5sec fuel pressure gauge shows 58psi but after starting gauge shows 52psi at idle. Rev engine the throttle pressure drops to 48-50psi. When rpm falls pressure shortly goes up to 53-54psi and then back to 52psi again.
Wire from stealth 340gph to fitech orange wire is 12-15 feet done in 4,5mm2 equal to between 10-12ga, could this one be to small?
Again thanks for your help.
Regards Morten
What is your PWM set at?
Yep, got the pics. Not sure why it couldn't upload.
If you have full pressure when key on, then the pump and regulator are working. Must be a restriction on your feed line. That pump should keep up with out issue. May check ground for pump.
My 340 keeps pressure at 60 PWM
Great, I'm sure it's not your site but it's my phone, I'm having this problem sometimes, yesterday i did SMS pics to wife's phone and it worked (i tried to send from both my email and wife's email from my phone and it didn't work) as i said to wife, I'm needing new phone 😃
Back to topic... great to know that settings in PWM is okay, but what could then cause this pressure drop??
As I wrote fuel gauge shows 58psi when key is turned on and pump is building pressure, but when engine runs is dropping. Fuel line is AN-06 as recommended from Aeromotive and w return line. Ground is done in same 4.5mm2/10-12ga.
I could understand it was electrical issue or fuel restriction related if pressure never gets 58psi, but it seems strange it ok under "prime" but at continuous use it drops, that's why in my world it seems more like a unit issue, but I'm not a pro..
But I'll check fuel line again and wiring, and if you figure out other ways to failure test, please let me know.
Are you using a relay between orange wire from unit to + on pump? Fitech writes that it ain't necessary.
What size of wire are you using to + and how is yours connected?
What size of fuel line are you using?
Again thanks for your help, I appreciate that.
After measuring positive and ground wires used at fuel pump and looking for same wire size in shop I found out that used wire is 6mm2 or 10awg.