Injector duty %

boostedeh2 · Post by **boostedeh2** » Fri Jan 09, 2009 2:30 am

stock gsr with t3/t4 60trim precision 880cc stock fpr walbro 255lph at 12psi the injector duty is already showing 94% at 14psi its showing 120%, the car is not leaning out...How accurate is this or my settings are wrong so its showing the wrong values?

Post by **Gaskleppie** » Fri Jan 09, 2009 3:11 am

It was quite accurate! Didint hear calvin he has changed it so.... I had this also once. Broken B&M fuel regulator! It leaned out at 130% then...

boostedeh2 · Post by **boostedeh2** » Fri Jan 09, 2009 4:11 am

It just doesn't make sense to me that 880cc is already at 94% on 12psi on a stock gsr though...at 14.47psi injector duty is at 122% and a/f is at 11.84.

Post by **calvin** » Fri Jan 09, 2009 8:07 am

what is your offset or overall fuel trim

boostedeh2 · Post by **boostedeh2** » Fri Jan 09, 2009 11:03 pm

calvin wrote:what is your offset or overall fuel trim

offset is 49 overall fuel trim 0.

Post by **Gaskleppie** » Sat Jan 10, 2009 5:48 am

It just doesn't make sense to me that 880cc is already at 94% on 12psi on a stock gsr though...at 14.47psi injector duty is at 122% and a/f is at 11.84.

Like I said. I had this also once and it turned out to be a broken FPR. Fuel pressure dived like a stone in free air..

JaredKaragen · Post by **JaredKaragen** » Sat Jan 10, 2009 11:12 pm

Just to note since it's relivant: I would say about 75% of the OEM FPR's I have run across have not responded to vacuum; needing replacement. out of these cars, I would say 99% of them had idle and idle/afr issues before but not after replacing the FPR with a brand-new one.

boostedeh2 · Post by **boostedeh2** » Sat Jan 10, 2009 11:47 pm

hmm I'll try to find one to replace it..thanks!

boostedeh2 · Post by **boostedeh2** » Sun Jan 11, 2009 6:20 am

I put on a different fpr with the B&M fuel commander on and the car does feel smoother but still showing around 116% injector duty.

Post by **Bugermass** » Sun Jan 11, 2009 6:58 am

dutys are off.. I've been sayin it for a while.

boostedeh2 · Post by **boostedeh2** » Sun Jan 11, 2009 7:01 am

Bugermass wrote:dutys are off.. I've been sayin it for a while.

glad to hear that, now I can rest knowing that my injectors won't blow up

Post by **Bugermass** » Sun Jan 11, 2009 2:24 pm

just keep an eye on your injector durations. 16ms @ 8000 RPM is jsut about wide open on a 4 cyl ..

boostedeh2 · Post by **boostedeh2** » Sun Jan 11, 2009 3:25 pm

Bugermass wrote:just keep an eye on your injector durations. 16ms @ 8000 RPM is jsut about wide open on a 4 cyl ..

I just checked the log again and its showing 17.12ms 113% at 16.27psi@7944. So how exactly do I fixed this problem? Do I need bigger injectors?

Post by **Gaskleppie** » Sun Jan 11, 2009 6:08 pm

16ms @ 8000 RPM is just about wide open on a 4 cyl ..

I just checked the log again and its showing 17.12ms 113% at 16.27psi@7944.

So the dutycycle is not far off then....

Post by **Bugermass** » Sun Jan 11, 2009 6:28 pm

Its not the duty cycle then, it has to be something with the way injector pulse width is calculated. OR mabey because o differences in impeadances with resistor boxes and what not the injectors arn't really active for the INJ PW that the ecu is commanding.. I don't know, but somthing is not correct..