How too see my injector duty cycles????
 

I have LT1 comm. and also A tech1 scan tool But I do not see the duty cyles anywhere. Am I overseeing them with these tools????

Duty cycle is not a native data item from the PCM and must be hand-calculated based on RPM and injector pulse width. Or, you can get datamaster, which does this for you and displays it along with all the other PCM data.

Go to http://www.ttspowersystems.com and download the software - it is good for 20 free recordings.

Gary

How do I calulate this. Formula?

i use datamaster and like said before it tells you the DC. the only prob is that it is OBD I only. what year is your car?

also, were you at the Gathering? your car looks like the one that went off the road. if it is you, i take it everything is fixed?

Duty cycle equals pulse width, divided by the amount of time available in one 4-stroke cycle of the engine, times 100.

Available time in milliseconds equals:

120,000 / rpm

At 5,000 rpm, that would mean:

120,000 / 5,000 = 24.0mSec

If your pulse width at 5,000rpm was 18.0mSec:

Duty cycle = 18.0 / 24.0 = 0.750

0.750 x 100 = 75.0%

To generalize:

Duty Cycle = (Inj PW x 100) / (120,000 / rpm)

Thanks for the formula. My pulse widths stayed around 15.2-15.76. It looks like it is keeping me around 65%-78%. Thats is good correct.?I would like to send my log run and have a second opinion?


That was my dumb ass in atlanta that ran off the road.Luckly I was not going too fast due to loosing traction off the line. I only had to replace the (2) front wheels and 1tire,right lower A-arm,Bottom front ground effect and have the front bumper painted. i guess I can call my self lucky. I did throw those bald ET streets in the trash when I got home.

later :D

glad to hear you got it fixed!

I will look at the logs if you send them to me. Just be sure they are in ".csv" format.

Fred