Fuel delivery or Fitech Issue
Hey Guys,
I just put a Go 600 on my newly rebuilt Cadillac 429. I have the Fitech 5001 external fuel pump kit.
The car ran amazing for about 250 miles. Then it started to starve for fuel. It will run good for about 2 or 3 miles and then slowly choke out.
The fuel pump seemed unusually loud so I replaced it. No change.
I also tried running it without the cap on to make sure my vent was good. No change.
Here's the WEIRD thing. When it chokes out and won't run, I can reload the default tune from the handheld unit into the EFI brain and it will drive good again for a few more miles and then repeat the cycle.
I do not have a fuel pressure gauge but this makes me think there might be a Fitech issue rather than a delivery issue and I just wanted to see if anyone has any ideas before I start ripping the fuel system apart again.
Could this be a fuel pump PWM issue? If so, anything else I can try?
I had a bung welded to my fuel tank and the tank was completely clean when reinstalled. So I don't think it's s filter issue or anything of that sort.
Thanks in advance!
I would start with a fuel pressure gauge. Also watch data.
Any way you can share your settings? I also have a 429 Cadillac but Im having trouble getting it dialed in.
Thanks.
My settings are for a mild 350. Would not work for your engine. The default settings are good enough to work the bugs out. The issues you are having are not tune related. Most likely something in the install or design of the fuel system.
Sorry for the confusion, I was requesting the settings from Ali. We are running the same engine.
I ended up replacing my fuel tank ($400) and got an in tank pump ($300) and that solved my issues.
Im just running the stock software and the car runs awesome. Huge improvement. More power, smoother and quieter.
Only issues I’m having is the car runs cold blooded. I have to manually warm it up with the accel pedal. I have gone back and forth a few times with Fitech support but the changes they recommended didn’t do much.
We are investigating a noisy rpm signal now to try and track it down.
Even with the cold blooded issue, it’s totally worthwhile. It runs night and day better than it ever did with a carb.
lmk if I can answer any more questions.
Hello guys I too have a 429 Cadillac and installed a fitech and having issues wonder what modifications you guys made.to your cars tk get it to function properly