TPS vs MAP load sensing for ACC Enrichment
 

Wolf 3.1.

Right now, I am using the TPS for ACC enrichment purposes. My issue, though, is that I cannot get my S4 TPS to read lower than about 31. It reads from 31-99 right now, which I'm sure is affecting driveability somewhat.

I was thinking about using the MAP sensor for that purpose as well, and not just load sensing.

Just wondering if anyone had tried both methods....?

wanna bet we will be the only 2 to ever post in this forum?? :)

Anyhow, I know I posted this on the wolf list a little while ago, however I was on glue that day and wasn't tihnking.. I was looking at the wolf ver 4 manual and saw that it suggested MAP/MAF for load sensing with the wolf ver 4.. My bain translated "load sensing" into "accel enrichment" for some stupid reason and I ended up asking a real silly question that I already knew the answer to :(

Anyhow, I have tried both TPS and MAP for accel enrichment and I have gone back to TPS.. when I was using the MAP sensor for Acel, I found that I found get an initial hesitation whenever I quickly got on the gas during low vac low rpm situations..I attribute this to the MAP sensor seeing the quick change of + pressure when you step on the accel which then drops back down to vac.. I also found that when using the MAP for accel, you had to turn up the ammount of enrichment much higher than when on TPS..

I modified my s4 throttle body to use an S5 full range TPS arrangement and found that this setup gave better results than using the narrow range s4 setup, smoother in throttle transitions.. however I think I'll try using a diffrent TPS all together come the spring, somthing like the rotary GM type since I find that the mazda TPS's tend to go bad quite quickly..
As for you min tps setting being at 31, have you tried to turn the adjustment screw on the throttle body? the one you use to set the TPS on stock cars? .. by turning the adjustment screw counterclockwise, the plunger on the tps moves forward with each turn, lowering your min TPS reading.. you can actually get the tps reading to 0 if you want... turn the screw until the handunit reads 0, then hold the accel pedal down all the way and adjust the dashpot on the wolf ecu to read 98.. and you should be good to go...

Haha...our own personal Forum, lol.

Yeah, I figured you made a typo, since we use MAP load sensing already.

As far as turning the TPS adj screw on the TB. Yep, I have tried that. And it doesn't go much lower than 31. After that, I'm pretty sure the TPS plunger is actually separating from the little lever is rests on, and the readings don't go down any further. At least, that's what I think is happening...:confused:

Hi guys. Don't mean to poke into your personal forum here :-), but I just ran across this thread while searching for the volt/psi relationship for the stock map sensor...

I'm in the Megasquirt world of efi, and we've recently been discussing a similar issue, with one guy ( a 12a efi guy!) coming up with a code variant that allows map-based accel enrichment.

It seems if you've got the stock progressive linkage in your TB, then it takes a decent bit of rotation of the primary shaft to increase map because you are opening one butterfly only. This relatively large rotation angle gives a corresponding tps input that seems to work well for accel enrichment.

Now if you have a throttle body that opens all butterflies at once, a very small rotation angle (and therefore small tps signal) results in a much larger map jump. In this case some folks find tuning accel enrichment based on rate-of-change-of map better.

I've tested both on the sychronized-opening TB setup on my 4-port 13b, and I prefer MAP-based on this install. On my FC with stock progressive linkage, I'm using TPS for accel.

Hope you don't mind me budding in... You probably knew all that stuff above anyways, but I thought I'd mention it as I just went through this testing in the last couple weeks.

Although you probably wont like hearing this, i reccomend upgrading to a 4.0. I had a 3.1 and went to 4.0 and its a BIG improvement for drivabilty and control. I believe Chris can get you a discount if you previously have owned a 3.1. Otherwise, contact him or a wolf retailer and see if they have suggestions.

Im glad they finally have a forum for wolf stuff, i just saw it today by accident!!! Yay!

Thought about upgrading, but until the Wolf gets datalogging, I think I will wait. So much other stuff to spend $$$ than an EMS upgrade :)

The 4.56 rev of the Wolf has the same type of Datalogging as the 3.1 does now.. with some more features I believe... (Cant remember off the top of my head im at work)

TPS issues do SUCK. It is a S4 issue not nessecarily the Wolf thing..
Some people have modified the way the TPS sits on the manifold to make it more functional..
On the several 3.1 cars I have done.. we were idling at in the 20 percent range.. load wise, and the TPS becomes non functional at prolly 3/4 throttle.
Soo yes it isnt soo perfect at the very high throttle settings.. but hasnt been a real problem sofar. (Been running 3.0 not 3.1 thats how old it is.. for like 4 years I think..)
The 4.56 idles at 11-12 percent load on the same car. BUT the TPS is still incorrect.
I am building a EP motor for the car next week.. and will address the TPS issue for that car.... probably make a new metal plate/shim that the TPS hits that has a shorter radius, and make the TPS sit closer so that Full throttle is actually 100% out on the tps, and closed is 0%