Vapor Lock or Failing Fuel pump
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So I have had some trouble with my car during temps above 180 degrees.
I ve had this problem ever since I installed my FF 640 cc injectors. Initially I had to add a bunch of fuel to even get my car to start when I installed FF640 (following OGPedxing install video). My non miata car friend thinks its vapor lock. But through research it isn’t very common on a stock miata fuel system unless something is failing; vapor lock is more common in low psi systems like carburetor systems. I am hoping someone can look at my logs and tell me if they see a symptom I am missing. I have a DW 200 I am going to install and was thinking I would replace the fuel filter and maybe the fuel pressure regulator. Honestly I am still learning how to diagnose with megalog viewer.
I am running a slightly modified base map. Just trying to get it pretty close before I get it on the dyno.
I am thinking my Fuel pump is failing and was fine for stock miata but can handle the new injectors. If the fuel is vaporizing in my lines the pump can’t overcome the pressure.
MY MAIN CONCERN is that theres something wrong with my tune and not hardware. I am hoping someone can look for glaring things and tell me to just Learn to Tune.
Current mods.
MK complete kit. (MS3 PNP PRO, FF 640, CSF radiator, Supermiata Reroute)
Mac EBC
Plans:
DW200 install (waiting on the wiring connector to show up)
March 2020 Dyno date
Thank you in advance
I ve had this problem ever since I installed my FF 640 cc injectors. Initially I had to add a bunch of fuel to even get my car to start when I installed FF640 (following OGPedxing install video). My non miata car friend thinks its vapor lock. But through research it isn’t very common on a stock miata fuel system unless something is failing; vapor lock is more common in low psi systems like carburetor systems. I am hoping someone can look at my logs and tell me if they see a symptom I am missing. I have a DW 200 I am going to install and was thinking I would replace the fuel filter and maybe the fuel pressure regulator. Honestly I am still learning how to diagnose with megalog viewer.
I am running a slightly modified base map. Just trying to get it pretty close before I get it on the dyno.
I am thinking my Fuel pump is failing and was fine for stock miata but can handle the new injectors. If the fuel is vaporizing in my lines the pump can’t overcome the pressure.
MY MAIN CONCERN is that theres something wrong with my tune and not hardware. I am hoping someone can look for glaring things and tell me to just Learn to Tune.
Current mods.
MK complete kit. (MS3 PNP PRO, FF 640, CSF radiator, Supermiata Reroute)
Mac EBC
Plans:
DW200 install (waiting on the wiring connector to show up)
March 2020 Dyno date
Thank you in advance
Last edited by Nordz; 02-02-2020 at 05:05 PM.
#2
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Our cars don't vapor lock. They do have hot restart problems if the IAT sensor is installed behind the radiator. Should be in the cold side area of the intercooler or piping behind the bumper or the wheel well area. Tune can make a difference too, but I can't see yours right now because I'm using the mobile app.
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