Fuel cut during wot on straight.
Thread Starter
Senior Member
Joined: Aug 2021
Posts: 398
Likes: 130
From: SoCal
16' C63s, 22' RAM 1500
Fuel cut during wot on straight.
So I was exiting the last corner then went onto the straight halfway down my fuel cut off.. got a cel you know.. drove off the track.. got escorted out by the safety truck and scanned the car.
forgot the actual codes but one was a fuel pump issue.
anyone ever tracked their car on 103F degree weather and have fuel pump issues? Also marked both banks running lean as well.
All temps where okay nothing to worry about which includes:
water temp.
oil temp
and transmission oil temp.
I let the car cool down for a bit, erased the codes and went on my happy merry way home pondering why that happened? (2.5 hour drive home btw)
drove home fine (last Friday) and until today it’s been great. New issue non related but still popped up a cel.
anyways ordering a new fuel pump and some other goodies for todays cel. (Control valve solenoid).
forgot the actual codes but one was a fuel pump issue.
anyone ever tracked their car on 103F degree weather and have fuel pump issues? Also marked both banks running lean as well.
All temps where okay nothing to worry about which includes:
water temp.
oil temp
and transmission oil temp.
I let the car cool down for a bit, erased the codes and went on my happy merry way home pondering why that happened? (2.5 hour drive home btw)
drove home fine (last Friday) and until today it’s been great. New issue non related but still popped up a cel.
anyways ordering a new fuel pump and some other goodies for todays cel. (Control valve solenoid).
Senior Member
Joined: Dec 2021
Posts: 268
Likes: 135
From: Maryland
2018 C63s
So I was exiting the last corner then went onto the straight halfway down my fuel cut off.. got a cel you know.. drove off the track.. got escorted out by the safety truck and scanned the car.
forgot the actual codes but one was a fuel pump issue.
anyone ever tracked their car on 103F degree weather and have fuel pump issues? Also marked both banks running lean as well.
All temps where okay nothing to worry about which includes:
water temp.
oil temp
and transmission oil temp.
I let the car cool down for a bit, erased the codes and went on my happy merry way home pondering why that happened? (2.5 hour drive home btw)
drove home fine (last Friday) and until today it’s been great. New issue non related but still popped up a cel.
anyways ordering a new fuel pump and some other goodies for todays cel. (Control valve solenoid).
forgot the actual codes but one was a fuel pump issue.
anyone ever tracked their car on 103F degree weather and have fuel pump issues? Also marked both banks running lean as well.
All temps where okay nothing to worry about which includes:
water temp.
oil temp
and transmission oil temp.
I let the car cool down for a bit, erased the codes and went on my happy merry way home pondering why that happened? (2.5 hour drive home btw)
drove home fine (last Friday) and until today it’s been great. New issue non related but still popped up a cel.
anyways ordering a new fuel pump and some other goodies for todays cel. (Control valve solenoid).
*****Fuel vapor lock from cavitation at the pump, or possibly not enough fuel in tank causing the pump pickup at the tank to suck up some air in addition to fuel. Sensors read lean for a few secs and the car auto safety shuts things down to protect the motor/car. 103 is hot ambient and it is hotter under the hood and easy for the fuel to percolate a bit, and cause issues with pressure at the HP pumps up front due to excessive heat and the fuel basically over atomizing through the high pressure pumps or at the injectors.
I've never had this happen on my C63s but have had this happen on other platforms racing around at Summit Raceway in 100+ degree weather. I've had to use insulator wrap on the fuel lines under the hood before, or re-route away from hot headers, or a big turbo sometimes. If the car has some miles on it, the fuel pump filter(s) might be a bit dirty and should be replaced if you are racing. It doesn't take much crap in your tank over time to reduce flow rate enough that along with heat could cause problems. Few people race their cars so they never experience these type of high heat issues.
Good luck. It's smart to replace a cheap fuel pump versus a really really expensive motor!
Thread Starter
Senior Member
Joined: Aug 2021
Posts: 398
Likes: 130
From: SoCal
16' C63s, 22' RAM 1500
*****Fuel vapor lock from cavitation at the pump, or possibly not enough fuel in tank causing the pump pickup at the tank to suck up some air in addition to fuel. Sensors read lean for a few secs and the car auto safety shuts things down to protect the motor/car. 103 is hot ambient and it is hotter under the hood and easy for the fuel to percolate a bit, and cause issues with pressure at the HP pumps up front due to excessive heat and the fuel basically over atomizing through the high pressure pumps or at the injectors.
I've never had this happen on my C63s but have had this happen on other platforms racing around at Summit Raceway in 100+ degree weather. I've had to use insulator wrap on the fuel lines under the hood before, or re-route away from hot headers, or a big turbo sometimes. If the car has some miles on it, the fuel pump filter(s) might be a bit dirty and should be replaced if you are racing. It doesn't take much crap in your tank over time to reduce flow rate enough that along with heat could cause problems. Few people race their cars so they never experience these type of high heat issues.
Good luck. It's smart to replace a cheap fuel pump versus a really really expensive motor!
I've never had this happen on my C63s but have had this happen on other platforms racing around at Summit Raceway in 100+ degree weather. I've had to use insulator wrap on the fuel lines under the hood before, or re-route away from hot headers, or a big turbo sometimes. If the car has some miles on it, the fuel pump filter(s) might be a bit dirty and should be replaced if you are racing. It doesn't take much crap in your tank over time to reduce flow rate enough that along with heat could cause problems. Few people race their cars so they never experience these type of high heat issues.
Good luck. It's smart to replace a cheap fuel pump versus a really really expensive motor!
Also The car does have 115kmiles already
I’ll be purchasing that new fuel pump as soon as I get a response from FCPeuro
