Ecumaster forum

How do you your properly calibrate the acceleration encrichment? As far as i can see it there are two tables that needs to be set. dTPS rate and TPS factor.

I have a lean spiking issue when accelerating the accelerator in the 3-20% area.

Most problems with acceleration enrichment can be solve with proper VE tuning. Slow engine reaction to sudden kick of throttle on idle is because short lean state on low RPM. Usually customers build flat map from vacuum when engine is idling to atmospheric pressure. It is mistake, VE after idle rise suddenly.

My method for acceleration enrichment in idle set up is:

Turn acceleration Enrichment off in: Enrichments -> acc enrichment " enrichment limit 0"
Next I open log with MAP, RPM, TPS, AFR, VE, TPS rate, ACC Enrichment, Acc Enrichment PW.
Logging AFR rpm VE nad TPS, I open throttle slowly a little, and try to correct VE table so that Engine react for throttle opening with out delay. Then I open throttle little faster and little bit more to rich less vacuum, and correct VE table again. I use this procedure till the throttle response will be good. You have to check AFR and make corrections to VE map.
Then I set acceleration enrichment to 100%, and watch reaction of the engine to throttle opening. Watching TPS rate I see percent of acceleration enrichment set in table. Modifying ACC Enrich. % I try to reduce lean spikes that leads to slow engine reaction for throttle opening. Usually Good VE map is enough.

Another thing is ACC Enrichment during higher RPM's and load. But first You have to build VE map for almost all state of the engine (vacuum, atmospheric pressure, boost in all RPM range). Then You check log how AFR look like during sudden throttle opening, which can result in engine choking after gear changing, knocking ....




In Log window You can see How much PW ACC enrichment add to Injector PW based on TPS rate and values set in ACC enrichment table.

Excellent write-up, This should definatly be a sticky. Have you considered writing a tuning-guide?

I see that my tps rate-numbers are very low. What could be the reason for this? Checking previous logs i never find numbers higher then 25.

In Sensors/ TPS there is an option dTPS interval.
You can increase the number so it will increase dTPS rate

Do you think that this will help in my case , I mapped 2 bmw with EMU one with m50 turbo - there is no problem with acceleration enrichments , but on mine E36 S38B38 Alpha N with 6 50mm throttle bodies I do have huge problem , see how I play with pedal to make the car not cut , also there is tps spike after I change gear at about 7000rpm , I do not tocht the gas pedal and do not know why is this spike I change gear and leave it deccelerate .... As you see the acc rate % maximum is about 3-4

to be honest i would start from "tidying up" VE map and then start sorting out acceleration enrichment..

Does this look OK? Are those lean periods after blipping the throttle normal?

Try to upgrade to 1.120 version.
There are some improvements for acc enrichment that should make tuning of it easier.
There is also option to batch all injectors when acc enrich (once) that helps a lot with acceleration lean condition.

I can only find V1.1, is that the latest version?

www.ecumaster.com/tv

Before firmware upgrade please save your project.

I have now uploaded the latest software. I have attached the setup and a log. It looks way better than before, but i still get a narrow spike. 18AFR at 120 kpa sounds scary.
I also get a small hesitation when flooring it. A short stutter before it starts.

I have now spent a few hours tuning the VE map for 20-100 kpa. But no matter what i try, my afr is all over the place when i am not holding the throttle steady.

Show me your VE. Do you notice anything on the engines performance or is it just that you see it in the log?

The throttle respons feels very good now. It is just the logs that looks bad.

I see the formula for enrichments - Acc enrichment = Dtps rate * RPM * TPS factor * Clt factor - can you give me example with real numbers and how to use result as % or PW ? for example - ACC = 110 * 65 * 70 * 100 ( not used clt factor ) .