Rich transient fuel condition

[toast]

All,

In the process of tuning my Edelbrock kit with Zach from CSG. Everything is pretty much dialed in, but we have an issue with throttle transients from a stop. He has already removed over 30% of the fuel from the transient tables but when leaving a stop my AFR goes very rich for a second before recovering. This causes a very slight but very annoying stumble when taking off from a stop. Zach suspects one of my injectors may have a small leak since the fueling is dead on when driving normally. I'm going to get a pair of new injectors and start swapping them out one side at a time.

Anyone else ever run across this?

[steve99]

Do you have fairly large port injectors fitted ?


If you have aftermarket pump fitted check fuel pressure isnt too high should be arround 60psi



Try running 100% direct injection only till say 0.7 load if its not already done.

[toast]

Everything is stock.

I'll let Zach do the tuning parts, just wondering if anyone ever had experience with a leaking injector and what the symptoms are.

[toast]

That makes sense, thanks.

[Mr_Eyo]

Originally Posted by toast

All,

In the process of tuning my Edelbrock kit with Zach from CSG. Everything is pretty much dialed in, but we have an issue with throttle transients from a stop. He has already removed over 30% of the fuel from the transient tables but when leaving a stop my AFR goes very rich for a second before recovering. This causes a very slight but very annoying stumble when taking off from a stop. Zach suspects one of my injectors may have a small leak since the fueling is dead on when driving normally. I'm going to get a pair of new injectors and start swapping them out one side at a time.

Anyone else ever run across this?

I've got the same thing. Large IPW and retarded timing starting on the gas. 2017 AT. Not sure anything can be done since it prevents knocking.

[freerunner]

Originally Posted by Mr_Eyo

Large IPW and retarded timing starting on the gas.

Load limits ok, not too high?

[toast]

Originally Posted by Mr_Eyo

I've got the same thing. Large IPW and retarded timing starting on the gas. 2017 AT. Not sure anything can be done since it prevents knocking.

Who did your tune? Zach said that the richness that he sees in my log is not on purpose and not normal. I thought the small stumble I always felt leaving a stop was me not being able to drive with the new clutch until I caught it one particularly cold morning when the car was outside. Just giving it a little gas while sitting still made it almost stall and I caught it in a log.

[steve99]

Originally Posted by toast

Who did your tune? Zach said that the richness that he sees in my log is not on purpose and not normal. I thought the small stumble I always felt leaving a stop was me not being able to drive with the new clutch until I caught it one particularly cold morning when the car was outside. Just giving it a little gas while sitting still made it almost stall and I caught it in a log.

Racerom​ 10 had a bunch of strange bugs. Racrom 11 fixed quite a few. But racrom 9.1 seems reliable but lacks some of the advanced features of 10/11 like closed loop fueling and intergrated flex.


But might be worth trting to get tune using racerom 9.1 if you think everything mechanical is ok