Thread: Did Some Datalogging, Now I have some questions

Ok so I finally got to messing around with my calum basic ecu.

I just have the stock 94 ecu program.

I used ECUTalk to look at the parameters, and did some logging while idling.

I noticed that my rpms would fluctuate between 780-850 at idle. Is this bouncing normal for everybody else?

One other thing that I noticed was that my timing at idle would bounce around mostly between 13 and 15 degrees. At some points it went up to 17 and a couple of points showed 11 degrees. I'm thinking something isn't right with all the bouncing my timing does. Any thoughts would be welcome.

The RPM fluctuation is normal.
The timing fluctuation at idle is also normal -- the ECU adjusts the timing to help keep the idle steady. If you put the ECU in "set timing mode" then the computer stops adjusting the fuel flow and timing to steady the idle speed. As a result, you can set your base idle and timing.

Remember, the ECU assumes that base timing is 15*, no matter where you set it with the distributor. So don't expect the timing that you see with your software to change when you turn the distributor to set the timing. You have to use a timing light.

Ok good to know. Thanks billc

You bet. I just got some incredibly helpful advice tonight on installing gauges. So what goes around comes around. That's why we are a community.

Bill