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Hello everybody,

I'm new on this forum from France (sorry in advance for my English )
I finally make my first race with my new DTA S40 last weekend after long months of waiting. I’m really happy with the result and I have some questions.

I recorded the CAN values during all the meeting and found a strange result on injection time at idling (TPS at 0%)

On the picture below the blue curve is the recorded CAN value (0x2003-3) and the red one the expected value according to my calculations (with TPS/RPM table entry and compensation for air&water temp and battery).
We can see that the results are quite the same expect during transient on TPS. Really good starting point. On the second picture color are the same and I add TPS in green. At 0% we can see that there is instability on the injection time (left part).
It jump from 2.53 to 1.73 (about 32% reduction there is no jump in the injection table) and disappear at 1% TPS (right part). No lambda loop and no idling regulation activated. It’s look like transient reduction but pedal don’t move. I put the throttle sensibility at 10% for 10ms so I don’t think that it could be this.
Have you any clues or advices?
Thanks for feedback
Regards

what rpm was this at? and do you see the same on the real-time chart?

idling around 1700 RPM ±100 for stability.

I don't know on the real-time chart.
I'll give it a try this weekend, car is not at home.
Thanks for the idea.

Hi,

Not reproduced yesterday in real time mode. Injection time look stable.

Because I’m a little bit stupid I forgot the sd card of my logger to look at both in the same time...
Need an other test from my side.

Does your logger have a spare channel that you could log the injection PW directly not over the CAN?

Rob Stevens wrote:Does your logger have a spare channel that you could log the injection PW directly not over the CAN?

Yes but I don't have the time for this now
(Edit : the requested channel frequency to see something is more a problem !)

The second race planned for next weekend. I'll give a look to the logs and the real time screen on the same sample.

I'll keep you informed

Sad news....

The engine started to smoke blue during time trial last week-end...
I stopped the race before making more damages.
I’m not able to perform more tests for the moment.

It’s now time for a full rebuild.