TPSdot Tuning
 

Anyone have some good info on settings or how to adjust TPSdot? The directions i found didn't work to well for me. Not sure exactly what I'm doing with it I guess.

scour the ms forums for settings to start with and tweak from there.

datalogs will help you a lot. if it's anything like other ems, it's used to prevent lean conditions when you jab the throttle.

start a datalog and in low gears (2nd is fine probably), step on the gas pedal at varying rates. start with a stomp 0-100% tps in <1sec then go up from there. you probably wont need it when it takes more than 2-3 seconds to floor it.

then look at the datalogs and watch where the TPS changes (you flooring it). if there's any change in the AFR. as the lines get less and less steep, you'll notice less AFR change. where you flooring it has almost no effect on AFR is just above where you want to set TPSdot. pick the next steeper line and divide the voltage change by the time change for those voltages in your datalog.

(5-0V)/(20.3-18.7sec) = 3.125V/s for example would be your TPSdot.

Course I never used a MS so I don't know if that's how they implement it but it should be similar.

Matt

I have TPSdot on my '02, working perfectly. I will pull out the numbers tomorrow.

Jim

Have you seen this thread?
http://www.msefi.com/viewtopic.php?t...ion+enrichment

I ran across this after I got a tune I was happy with so I never followed his method. Logging makes since but it never really worked for me either. Too noisy.

I'n running pure TPS now. Possibly a little lean but it's good enough right now.
(40,7),(18,4),(9,2),(3,0.7)

on most of my mazda setup it goes like this:

4v/s----------------3.0ms
3-------------------2.5
2-------------------2.0
1-------------------1.0

tpsDOT----------between 7-10

here's how you adjust it. Run low speed on 3rd or 4th gear, and accel different TPS value, I mean on the accelerator. Get fast on the pedal. You have to turn the realtime display screen on to understand the accel. When you give fast throttle, let say at 25-50%, the baud rates shoud not reach more than 1-2 v/s. When you snap wide open throttle the v/s should stay between 2-3. When you press the pedal in a linear accel, the v/s should stay low at 1. If the v/s isn't acting like this, you want to play with the tps dot value, so raise or lower it, but start at 8 (default setting) it shoud be close to where it has to be.

Now you get back to a AFR meter. Get the same test (fast accel, linear and low accel) and watch for the AFR, you want it to be stable as possible. So you watch where the blue reference going up. If the AFR is to lean so you increase the ms value at the corresponding v/s. Increase very little at a time, I mean by .1 or .2. You will notice a better throttle response fast.

You do the same with the cold accel. Let the amount to 100% and play with the enrichement ms.

Good luck

Attached is my msq; Stock '02 1.8/VVT with MonsterFlow intake.

Jim

Thanks Jim. I'll try it out when I get some time this week. School is being killer on my car time. Gotta get the good grades though.

Didn't realize MS1 was in volts/sec. My numbers are in (TPS%/sec,milliseconds).

Is the TPS linear? The cal only has values for 0 and 100% so I assume so.

Yeah the TPS is linear.

Bumping because I just figured this out...

In MegaLogViewer, open the "Calculated Fields" menu, go into "Optional Fields", and select TPdot. Enter your 0% and 100% throttle ADCs, and reload the log. Then you should be able to select "TPdot" as one of the graph lines.

I haven't done any tuning based on it yet, but the values it show seem to make sense compared with what I've seen on the bar graph in the Accel wizard.

-Mike