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Cold start running rich

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Having trouble with cold start on my honda b16 itb's. Running on hondata s300.

The afr's when cold are in low 11s. once up to temp its perfect.

Removed all ECT compensation but that didn't make a difference.

Ive attached a couple log files

Attached Files

Does the vehicle not have a cold start map?

Its perfectly normal for cars to run mega rich during cold start. I think some vehicles can go as low as 6-9.

If you consider, the richer the mixture, the more heat which is produced. Ultimately, reducing warm up time.

No cold start map on hondata, just the fuel compensation tables.

Im worried about getting bore wash running that rich on idle, or is low 11s not going to cause a problem?

Those two different graphs you have shown are a bit different in operating conditions.

One is 65 kPa @ 824 RPM and the other is 60 kPa @ 960 RPM, seems like your fuel map could be tuned to help the first area, while leaving the second area alone. But you need to do this with the engine fully warmed up.

Another thought -- you can put negative values in the compensation tables to reduce the fuel, why don't you try tuning that until you get the AFR you want.

Il try adjusting the fuel map see if that improves it.

I did put negative numbers in the compensation tables but that didn't make the slightest bit of difference which is strange.

I wouldn't say that the log file is necessarily an issue. In that log you're around 11.9:1 which is probably a touch rich but certainly not at risk of fouling plugs. I'm not sure why it's so much richer with no compensations but the fact you're running at two different load and rpm points (as David mentioned above) may be something to do with it.