FI-TECH needed help PLEASE DESPERATE
Le Mans Master
Joined: May 2003
Posts: 8,872
Likes: 3,548
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
Just did a test today when hot. Car always kicks over like it is going to start than dies. When I turn on key I hear pump but no gas at all. I think the first little kick is what might have been left over. I have turned the key numerous times activating the fuel pump with no gas in the throttle body.
1. Ecu bad and not allowing gas to come in. Doubt this because this is my second system that did exact same thing.
2. Fuel pump making noise but not pressure?
3. Adjust cranking 170 degrees numbers through hand held to dump more fuel on hot start.
4. Heat soak or vapor lock.
I guess first step step to get gauge and see what fuel pressure is then go from there.
1. Ecu bad and not allowing gas to come in. Doubt this because this is my second system that did exact same thing.
2. Fuel pump making noise but not pressure?
3. Adjust cranking 170 degrees numbers through hand held to dump more fuel on hot start.
4. Heat soak or vapor lock.
I guess first step step to get gauge and see what fuel pressure is then go from there.
Here's what a buddy of mine did to his 70 LS conversion...much better than a clock!!!
Drifting
Joined: Aug 2015
Posts: 1,939
Likes: 476
From: NSW, Australia
C3 of Year Finalist (track prepared) 2019
Sounds like you're on track. Check the pressure and get back to us. Can try adding some fuel to hot start and see if it helps. Have you tried using a little accelerator while cranking when it doesn't want to start, and if so does it help?
Racer
Joined: Mar 2019
Posts: 327
Likes: 75
From: west mi. / ms. gulf coast
What did you do to your fuel delivery system? Did you put the high pressue electric fuel pump in the tank? did you put a high pressure fuel pump in line? Where in the line? Did you retain the stock pump and ad the high pressure resivoir system up front? Did you ad a fuel filter ? Where? The FiTech system requires about 58 psi to run properly. Without a fuel pressure gauge you really don't know where to start looking. Vapor lock could be a problem , but I think it has something to do with fuel pressure.
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Melting Slicks
Joined: Jun 2006
Posts: 2,071
Likes: 147
From: S Nevada
Ive had a few issues with fuel injection. The long cranking on my 92 corvette was a bad fuel press regulator. The fuel press guage isolated that one. The other was on my 72 with the fitech, I swapped in a plastic AFR intake, the fuel pump constantly cycled on and off, car never started. Turned out plastic doesnt conduct electricity, duh, and normally the intake is grounded to the block, a separate ground strap to the base of the fitech body cured that. I just fired my engine yesterday after sitting since May doing upgrades. Ran perfectly. I like the fitech system, sometimes its just something we overlook.
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
Run the car cold to hot , Wait until you get to the wont start issue, Get in car and Press throttle wide open ,, Crank it over ,, does it start or attempt to start or start after a time cranking it ?
Thread Starter
Racer
Joined: Jul 2017
Posts: 399
Likes: 115
From: chico ca
Tried that and it doesn’t even want to start. Acts Like a carb with no gas.
Thread Starter
Racer
Joined: Jul 2017
Posts: 399
Likes: 115
From: chico ca
Update
Well I got a fuel pressure gauge and hook it up to fuel line before throttle body. To my surprise it read about 125psi. So that is pinned past the 100 psi so I figured I have a broken gauge. Get another gauge which I know is correct and again it pinned the needle at about 125 psi. FI -tech said to disconnect return line and see what happens to pressure.... stays at over 100 psi. So I put the other gauge on the return line end and that pressure was at 125psi.
I am no FI genius but pretty she 125psi is not good for any system. Waiting to hear from FiTech. I am just thankful none of the lines came apart when I was driving car!! I am also pretty sure this has a lot to do with my hot start problem.
I am no FI genius but pretty she 125psi is not good for any system. Waiting to hear from FiTech. I am just thankful none of the lines came apart when I was driving car!! I am also pretty sure this has a lot to do with my hot start problem.
Drifting
Joined: Aug 2015
Posts: 1,939
Likes: 476
From: NSW, Australia
C3 of Year Finalist (track prepared) 2019
Seems odd! So you have the return just flowing into a Jerry can or something? Is this while running? Or just priming? Is there fuel coming out through the return line? If not then I guess there's a problem with the regulator on the throttle body.
Pro
Joined: Apr 2012
Posts: 655
Likes: 114
From: Picton NSW
well it seems like you have checked just about everything ,
I have not read all the posts here so I may be out of line here.
the systems say fuel or spark problems .
if you have fuel to manifold then spend more time looking at the wiring to the coil.
remember you get power to the coil at start up from the starter if you are using the original system .
when you let the key go back to run you revert to the run wiring .
If at hot start you have heat sink problems at the starter you will have low voltage problems to the coil.
check the power to coil, at the splice in the harness, its just in front of the wiper motor just to the right of the distributer
while cranking you may find your problem
Bfit
I have not read all the posts here so I may be out of line here.
the systems say fuel or spark problems .
if you have fuel to manifold then spend more time looking at the wiring to the coil.
remember you get power to the coil at start up from the starter if you are using the original system .
when you let the key go back to run you revert to the run wiring .
If at hot start you have heat sink problems at the starter you will have low voltage problems to the coil.
check the power to coil, at the splice in the harness, its just in front of the wiper motor just to the right of the distributer
while cranking you may find your problem
Bfit
Pro
Joined: Apr 2012
Posts: 655
Likes: 114
From: Picton NSW
Read all the posts
I would think 125 psi in the return line is not good .
is it possible to get hydraulic lock in the injectors on a petrol injector..
bfit
I would think 125 psi in the return line is not good .
is it possible to get hydraulic lock in the injectors on a petrol injector..
bfit
Last edited by bfit; Sep 12, 2019 at 04:23 AM.
Thread Starter
Racer
Joined: Jul 2017
Posts: 399
Likes: 115
From: chico ca
Yes we took off return line and started car. Line was in bucket. FI tech has a regulator inside throttle body I think. Maybe that is not working or at a very high pressure maybe there is a bypass to let fuel by??? Or the high fuel pressure destroyed the regulator??? Will find out more when I talk with FI tech hopefully today. I wish I could just go get another fuel pump but pretty sure fI-techs pumps are special for their systems.
oh and yes went through all the spark, starter and voltage tests already.
oh and yes went through all the spark, starter and voltage tests already.
Le Mans Master
Joined: May 2003
Posts: 8,872
Likes: 3,548
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
Can you blow any pressure in the return line? Sounds like it is clogged/line kinked.
Just a guess- some injectors will not work with too high of a fuel pressure.
The other thought is with the too high a fuel pressure- the injectors would spray too rich and the O2 sensor is backing down the pulse time for the injectors,
Either or- you now know the problem- you'll get it solved!!!
Richard
Just a guess- some injectors will not work with too high of a fuel pressure.
The other thought is with the too high a fuel pressure- the injectors would spray too rich and the O2 sensor is backing down the pulse time for the injectors,
Either or- you now know the problem- you'll get it solved!!!
Richard