Cylinder Cutout after driving ~2-3 hours.

[fosiacat]

Hey folks, hoping to get some thoughts about this. I've been having an issue where i'll get a CHUG and some shaking and then limp mode.

Seems to happen after i've been driving around 2-3 hours. If i step on the gas more than ~40-50% i see my low pressure dropping, eventually to where i get cylinder cutout. If i pull over and stop, turn the car off and back on, it'll be ok for a while.. however the next day, I could go out and rip on it through town and not have any problems at all.

car is a 2011 335is. index 12 injectors installed about 2 years ago, plugs ~5,000 miles, oil is new, fuel pump is a fuel-it stage 2.

I've done a lot of reading on this, and I suspected it's the EKP overheating. I've purchased a new one (but i haven't installed it yet)

basically i wonder if anyone thinks it's the fuel pump, if there's a way to test the fuel pump for a long-term sort of issue... and i guess what fuel pump people have been successfully running with the stock EKPM3. i know EOSpeed makes a replacement, which i guess is an option but i'd rather not.

should i just throw the new EKP in there and keep the existing pump, or should i get a new pump too? can a fuel pump just get "tired" after 2-3 hours of driving and crap out?

thanks for any help

(happy to provide any additional information)

 

[SlowE93]

Hey folks, hoping to get some thoughts about this. I've been having an issue where i'll get a CHUG and some shaking and then limp mode.

Seems to happen after i've been driving around 2-3 hours. If i step on the gas more than ~40-50% i see my low pressure dropping, eventually to where i get cylinder cutout. If i pull over and stop, turn the car off and back on, it'll be ok for a while.. however the next day, I could go out and rip on it through town and not have any problems at all.

car is a 2011 335is. index 12 injectors installed about 2 years ago, plugs ~5,000 miles, oil is new, fuel pump is a fuel-it stage 2.

I've done a lot of reading on this, and I suspected it's the EKP overheating. I've purchased a new one (but i haven't installed it yet)

basically i wonder if anyone thinks it's the fuel pump, if there's a way to test the fuel pump for a long-term sort of issue... and i guess what fuel pump people have been successfully running with the stock EKPM3. i know EOSpeed makes a replacement, which i guess is an option but i'd rather not.

should i just throw the new EKP in there and keep the existing pump, or should i get a new pump too? can a fuel pump just get "tired" after 2-3 hours of driving and crap out?

thanks for any help

(happy to provide any additional information)

Keep it simple and swap EKP and evaluate.

 

[fosiacat]

my concern is that if it is the fuel pump pulling more current than the EKP can handle, it will just burn out the new EKP as well..

 

[NoGuru]

If you have the EKP, swap it, takes about 5 minutes. I have a Walbro 535 and Walbro 450 on HOBBS running off the EKPM3 no issues.
I do have active cooling on it though, which might help a little.

 

[fosiacat]

so you’re running the 450 off the EKPM3. OK. have you done any distance driving? 2-3+ hours? I just got a new ekpm3 and bought some cooling for it - little cpu fan, heatsinks, will put thermal paste on the bracket again too...
thanks!

 

[NoGuru]

They are both running from the EKPM3 but the 535 which is a Hellcat fuel pump is the primary. I have done 25 pulls in a row at the drag strip so.....

 

[SlowE93]

my concern is that if it is the fuel pump pulling more current than the EKP can handle, it will just burn out the new EKP as well..

Should be fine. Tons of people run walbro 450 off factory EKP w no issues.