90a surging

[Ausmat]

Hi gents
I was coming home from a fishing trip yesterday and one of my engines started surging between 3400 rpm and 3800 rpm, it would drop the rpm from 3800rpm to 3400 rpm for a couple of minutes then it would go back up to 3800 rpm for 5 minutes.
When it dropped the rpm to 3400 if I increased the throttle input enough i could get it to run back at 3800rpm but then after a couple of minutes it would take off and go to 4500rpm.

I plugged it in to the sds and no error code.

Has anyone seen this before?

Thanks in advance.
Matt

[Bikermanlarry]

90a surging

We have a 05 df140, and experienced similar problems. We cleaned all the battery connections thoroughly and it seems to have corrected the problem.
Sorry, I'm not familiar with your motor... have a good one!