During a log today found im over 100% injector duty cycle with the following mods:

- Brian Crower 272 Cams (+1/-1)
- Buschur filter kit
- Hallman Pro RX (set at 22 PSI)
- 3" Catless TBE
- Forge type RS
- 255 high pressure pump

In searching and speaking to another Evo owner, I should be looking at the low/high switch as it may not be functioning properly. Is there any way to test this without having a fuel pressure gauge? Any other things I should look at? IDC goes 100 + at around 6500 RPM and then knock occurs going between 1 and 5 counts and does not stop until I left off. Its very typical to see no timing advance in my runs... Ideas? Questions? HELP?

Thanks in advance.

Edit- I'd post a log, however my Mac keeps thinking an excel document is a movie and wont let me change it.

 

bump

 

Anyone help?

 

You remember to put the white spacer at the bottom of the fuel pump?

I didn't and the damn rubber bushing popped down and I went horribly lean thought I killed my car until i figured it out later that day.

 

Spacer is definentely there from the stock pump

 

Mabye its just in your tune, dyno tune? street tune?, also whens the last time you changed your plugs? also, this might not help you alot with this issue but would give you some other advice with your fuel system.

https://www.evolutionm.net/forums/sh...d.php?t=245064

 

its an eflash from TTP based on my logs. Plugs are brand new ngk's.

btw, I'm assuming you can not turn off the hi/low pump feature in ecuflash correct?

 

Thought maybe I'd ask, I notice the pump is only loud during cold starts then I never hear it... I know during cold start the fuel enrichment kicks in and adds 5 psi ... is it possible under boost its not boost referencing due toa bad FPR and bypassing instead the extra fuel the pump is sending?

 

Send us an email with the data and we will review it.

 

sent

 

Reviewed and the logs look good. There is nothing wrong with them. 100 is not the limit of injector duty cycle FYI. They can run 120+. Personally I don't pay much attention to them as we have plenty of 11sec cars on stock 560cc injectors. If we reach a point where we richen a map and it does not richen the actual AFR, that is when we pay attention.

The stock injectors are plenty large enough for anything you can do with the stock turbo.

 

How do you run over 100% duty cycle...I thought after that they go static.

 

Time for injectors

 

Injector duty cycle is an number calculated by your ECU, while trying to supply the proper amount of fuel for the air flow data from your MAS. Over 80% IDC, injectors start to become less accurate, and then go "static" (wide open all the time) which means that the computer has no further ability to regulate your fuel component. While some may be able to get away with it, it's sure not the recommended way to measure fuel.

On top of that, the ECU assumes that your fuel pressure is correct -- and uses that assumption to calculate the signal to the injectors. If your pressure cannot keep up with the volume needed, you will go lean. A fuel pressure gauge is the best way to know whether you are maintaining proper fuel pressures.