I would think so. Maybe fuel vaporizeing in return line? Did you have the return before efi?
CK5
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no there was not a return
Might be the issue. It seems like when the lines start to vaporize, it continues through out lines, very quickly lol. And I'm sure it's gotta be over 100* on the HWY when it died on you too?
105* and traffic
Pretty sure it vapor locking. Google "what temp does gas vaporize?" It's pretty surprising.
its says 180 and my engine is running at 175
And gotta think about hoses along frame that are near the exhaust too. I'm pretty sure it's hotter down by the fuel lines, do u have headers? Or stock manifolds. Plus your sitting in traffic with no wind carrying the heat away. Or pushing cool air into engine compartment and hot air out, just hot air being pulled in by the fan.
That's why I ran my exhaust on the drivers side, fuel lines on the passenger.
After dealing with this, I think that's one of the best things somebody can do in a build. Even with a carbed motor. Alot of constant over heating issues, and premature fuel pump failures that plagued me and others I've dealt with in the past, all makes sense now. Even when I first bought my k20 burb that I put the fitech on, had a constant over heating issue when climbing hills. Now I know why.
mine is ran on opposing sides also
This thread talks about vapor lock and the guy seems to have the same issues as me. It died again today after the settings were changed to what FiTech tech support told me. I adjusted the fuel pump pulse setting so that the pump would strain less
https://www.corvetteforum.com/forums/c4-tech-performance/3121738-efi-vapor-lock-huh.html
https://www.corvetteforum.com/forums/c4-tech-performance/3121738-efi-vapor-lock-huh.html
I thought I read gas will vaporize faster under higher psi and higher octane vaporizes faster
That goes against science. Raising the pressure of a liquid raises the boiling point.
It will atomize better when discharged too.
Fi Tech might just refund me for the pump and I may use a TBI tank and sending unit with an in tank pump
Alright guys sorry for taking so long to update. I talked to FiTech and they exchanged the pump out in hopes that it was a defective unit. After installing the new pump I noticed its a bit different (terminals and included hardware), but this pump seems to work. The truck runs great even below a 1/8th tank and has no fuel pump noise. Although everything seems to be working I do have to say that FiTech customer service is extremely slow and unresponsive at times.
Question: after starting the truck it backfires quite a bit until it gets up to temp, any suggestions on fixing that?
Question: after starting the truck it backfires quite a bit until it gets up to temp, any suggestions on fixing that?
Spoke to soon the truck had the same fuel starvation last night while I was out on the trail. Got it back home and still have no idea whats causing it. I moved the lines away from heat, checked the vent, checked for leaks, checked fuel filter directions and still cant figure it out. I am calling FiTech to see if I can bring the truck by today and have them check it out.
a fuel pressure gauge becomes very handy in this scenarios.......
I'm picking one up today
Went to FiTech today and they had a senior tech look at the unit and the fuel system. After an hour or so of troubleshooting they couldn't diagnose any problems. He also said he couldn't fix the backfiring issue. I put a fuel pressure gauge on it and it is running at 34psi at idle and 42 off idle. im wondering if the ecu is causing it or if the pickup sock is getting sucked in
I think you're supposed to be getting nearly 60psi. I know when I ran a factory TBI out of gas it was doing some backfiring. It sounds like you may getting fuel starvation.
I don't think the ECU could cause low fuel pressure. Flow yes, but pressure should be steady.
I don't think the ECU could cause low fuel pressure. Flow yes, but pressure should be steady.
