Afer installing my MAP sensor and going to closed loop, my load sites seem to be jumping around and I am no longer reaching 100% load sites. Top so far has been 70% Often at WOT I can go from 60% load to 50% back up to 70%. I will post a log later. Before the Map sensor the load sites climbed very progresively.

 

First question that comes to mind (for not hitting the 100 percent load site), is what is the max reading you have set on your parameters section regarding map? I experienced the same issue when I was first starting. My max maf reading was hitting 1500 hz, but the setting was for 1700 or 1800. This would not allow me to hit the 100 or even 90 percent load sites.

One of the issues is that the map reading is not as progressive as a maf reading. I have seen that I can hit a progressive map reading, and it may fluctuate up and down .4 psi within the progressive load to 22 psi. In other words it would ramp up to 16 or 17 psi and then incrimently go up and then back down, only to go back up. Know what i mean?

The progressive nature of the maf reading makes it a little easier in my opinion. Looking at it as a number from 0 to 1600, as opposed to -?? to 22, there is alot more room to move progressively. This is very similar to a wideband vs narrowband o2 sensor. 0 to 1 volt on a narrowband leaves you with less room than a 0 to 5 volt on a wideband.

I hope I was clear on this. My ADD is killing me.

 

I thought that b/c I have the load reference set to MAP and not MAF, my max MAF would not mess things up. I do have my Max MAF set high becuase I was having fuel cut issues a while back. I will go back and lower it and see what happens. Thanks

 

It doesn't have to do with the MAF reading, I think he was using it as an example..

Here's my experience with the MAP sensor..

You have to set the PSI to be something slightly over the max you will hit, I think default its 25psi so you'd probably only hit 70-80%

I did find a bug in an earlier firmware setting where if you hit OVER the setting (I set it to 19psi for example) you would go 70 - 80 - 90 - 100 - 90 (basically once you went over the limit, the load site went back down, I'm not sure but I think that was resolved..

Now, when you hit a boost spike, you're load site will likely be slightly higher, than when the boost tapers, so you'll find that your load sites might drop a column as you approach redline, since load reference is now MAP/RPM/TPS instead of MAF which is an airflow reading.. You can see where there's an advantage and disadvantage.. using MAP will allow you to predictably be within a particular load site, however using MAF will be a more true reading of air demand... The only time I'd recommend using MAP for mapping is if you are having alot of trouble getting a predictable tune with the stock MAF.. My solution was to use a more predictable MAF sensor.. But without that as an option, MAP is the next best thing.

 

The problem here is that I want to set my max MAP at like 26PSI for my alcohol map, but this seems to cause problems when I am not running that map. Do you think that I should just use MAF for load reference to avoid these problems?

 

Well, I think either way your going to have trouble either way, 26psi will also result in having to set your max MAF reading higher, so when your not running a 26psi map, your going to be tuning much lower load sites (70% or so) regardless.. I think your in a catch 22 if you plan on running boost that much higher than your regular tune, you've extended the range of the mapping so everything on your normal tunes will appear to be much lower load to the UTEC.

 

I was contemplating the same issue when I was thinking about the alky. I was going to tune, lets just say for an example, 0 to 70% load site for normal boost of 23 psi. The 80 to 100 load site will be for alky at 26psi. The maf reading would be, again as an example, 0 to 1500 hz for the normal, and an addition 300 hz for the extra 3 psi. This would set my maf reading at a max of 1800 hz, but I wouldn't hit the upper load sites unless the alky was switched on.

I also was going to insert an inline switch for the alky controller. This is so that the UTEC can control the actuation of the alky, by utilizing the solenoid on/off in the parameters section. Map 1 being the 'normal' tune, and map 2 being the 'alky' tune. I would then set the solenoid to come on at all times, but when I switch to map 2, I would then active the online switch.

Just a thought.

 

Ohhh I really like that idea. I was going to hard wire a real switch but this is a way better idea. Thanks