Dialing in MAF and LTFTs going nuts!
06-30-2008, 08:41 PM
#1
Dialing in MAF and LTFTs going nuts! I just got HPT a couple weeks ago and have been working on my VE table mostly, and have nearly got it finished. After the VE table I am going to recalibrate the MAF table, and went ahead and got a headstart on this by logging dynamic airflow.
There are two ways to tune the MAF table that I've seen. One is to use STFTs vs frequency, and the other is to use dynamic airflow vs frequency. I chose the later and got some pretty close numbers, but they arent perfectly dead on. How to I go about fine tuning that portion? In my log, its histo 11, histo 7 is frequency stft.
Second questions: My LTFTs seem to have a mind of their own. After making a small change, they swing upwards of 10-15 points! I dont know whats going on with that. Meanwhile my STFTs are pretty close to leveling out.
Suggestions?
There are two ways to tune the MAF table that I've seen. One is to use STFTs vs frequency, and the other is to use dynamic airflow vs frequency. I chose the later and got some pretty close numbers, but they arent perfectly dead on. How to I go about fine tuning that portion? In my log, its histo 11, histo 7 is frequency stft.
Second questions: My LTFTs seem to have a mind of their own. After making a small change, they swing upwards of 10-15 points! I dont know whats going on with that. Meanwhile my STFTs are pretty close to leveling out.
Suggestions?
07-01-2008, 07:40 AM
#2
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Are you tunning part throttle or full? If it is part throlle you can use STFT if the commanded Air/fuel ratio is 14.6. Once the commanded Air/fuel ratio is below that(rich PE MODE) you will need a wide band. I have filters in the histograms that put the trim info into one histogram and the wideband info into the an other.
