Quote from melvinjo on August 25, 2020, 3:22 pm

Update:

Checked for codes:  None

I did find the blue FITECH wire was lying on/crossed over two spark plug wires, which IAW instructions say NOT to do as this can cause signal interference:  I am hoping this is the cause, but it takes about 45 min of driving before the probems I stated starts.

I would think if it was signal interference from the spark plug wires, wouldnt it do it as soon as I started driving?

 

Quote from tony-muscle on August 25, 2020, 4:30 pm

Could it be something like vapor lock related to fuel getting hot after some time running it? Are the fuel lines going too close to the exhaust or a hot engine spot? Can you log the parameters when it starts happening so you can follow the AFR?

Quote from melvinjo on August 25, 2020, 7:39 pm

Maybe not vapor lock   Since the fuel is under high pressure?   Lines not close to heat source.  Ill try logging the AFR as you said if it happens again

Quote from tony-muscle on August 25, 2020, 10:45 pm

Depending on what type of fuel pump you have (and where is it located), vapor lock can occur before the pump unless you have an in-tank pump.

Quote from Fitech junk! on May 2, 2022, 9:15 pm

I had the same problem, had to send it back to Fitech something about fuel pump relay not working correctly, the sent it back with added relay and wire harness for fuel pump! a I cheated and ran another wire with a switch in the dash for fuel pump!

ps, still trying to get it to run after they sent it back! Fuel isn’t the problem now, I think Fitech is junk, and guess what they don’t call you back and I cannt wait hours on hold

 

Quote from SodaPop on May 4, 2022, 6:02 pm

Quote from melvinjo on August 25, 2020, 2:09 pm

Ive got the Master Kit, GO STREET EFI 400HP SYSTEM.   I'm using the included in line fuel pump feeding a middle of the line  GM 350 crate motor (300hp), MSD6al for spark, stock GM HEI.

This is the second FITECH I have bought, the other on my 440/71 Barracuda, and the Cuda has and still runs great after 4 years

Back to my problem.  Starts fine, runs fine, etc, until about 45 minutes or so down the road.  Then it bogs down will barley run until I pull over, then it dies...  If I wait about 5 min or so, it MIGHT start and run for another 5 minutes until it dies, etc, etc.........

Its weird:  When it is cutting out, Ill pull over and it dies.  Wait 5 min, and I might, or might not hear the fuel pump running.  When I DO HEAR the pump, it will start and run, for maybe 5 min, and the cycle repeats.......

My fuel tank is above the fuel pump level, and since the tank is under the passenger seat, the fuel lines (Feed and return) are fairly  short

I was thinking maybe a vacuum issue, so I removed the gas cap, no improvement

So I called FITECH and I wont even tell you how bad the customer service rep was...........  So......

1.  I got another FI TECH in line fuel pump.      No change
2.  Triple checked grounds
3.  Triple checked MSD6 with the MSD6  on my Cuda.  (I was thinking signal issues)  No change
4.  Fuel filters are clear, no blockage

Any help is appreciated.  Its on a 4 wheel drive, and breaking down AGAIN in the middle of nowhere is getting very expensive (towing) and risky

You have a bad ECU caused by heat. Also dont use Fitech Fuel pumps, they are chinese JUNK!!!!! Get a quality walbro which are made in the USA. Fitech has fixed alot of problems on the new design ECU's. The older version failed due to heat and poor soldering on the ECU board.

Quote from mudshark on May 24, 2023, 5:43 pm

I have the exact same problem.  Tried several different fuel pumps. (Inline)

Thought the same thing.  It must be getting heat soaked after time.

I sent it back to fitech, they claim they brought it to 260 degrees with no sign of failure. They returned it ,along with a new fuel pump relay.

And quess what.. it still does the exact same thing.

I'll be contacting them again, as well as watching here for updates.

Hope we can feel good about this fitech.  It sure runs great for that first 45 minutes or so.