detonation or anomaly

[isnms]

These spikes showed up in my EGT signal. It hasn't appeared in any other logs I've been taking over the past few days.

I was in 4th or 5th gear, cruising. Seems to be at a time of off throttle, pink line declines.

 

[CajunKenny]

What's the 'User 1' input?

 

[isnms]

It's VF

 

[CajunKenny]

It almost looks like you would've been going down hill; but, your RPM's stay constant. It looks like a sudden loss of data/input because it starts to recover.

I doubt detonation. Could it be a loose connection...did you use wire taps for the install?

 

[mkIIIman089]

At <10&#37; throttle I'd say it's impossible for it to be detonation. Might just be noise... IIRC EGT sensors are especially susceptible and what ever set of events you created there made it go squirrely.

It does seem a bit strange that RPM is so perfectly flat without knowing what you were doing. I doubt any of this has anything to do with power loss to the ZT-2 though, from my experience if it loses power even momentarily it takes a minimum of 15 seconds for it to reboot again. During that time no logging can take place.

 

[tissimo]

Could be uneven burn through the cylinders and very low load.

 

[isnms]

Thanks for the replies. I'm thinking some kind of noise or signal distortion. I've taken over 80 minutes of logs over the last few days, to and from work normal driving, and this is the first time I've seen this show up.

tissimo - What are the conditions/cause/ramifications of uneven burn at low load?

 

[tissimo]

Thanks for the replies. I'm thinking some kind of noise or signal distortion. I've taken over 80 minutes of logs over the last few days, to and from work normal driving, and this is the first time I've seen this show up.

tissimo - What are the conditions/cause/ramifications of uneven burn at low load?

uneven manifold distribution at very low velocity, uneven injector flow, improper tuning for those very low load levels.

 

[adampecush]

how many seconds elapse on the x scale on that graph?

Looks like noise to me. You weren't monitoring your timing by any chance were you?

 

[isnms]

The duration with distortion is about 5 seconds.
No, i don't have a way to monitor timing.