Lean spike on tip-on, not due to lack of AE
 

*tip-in, not tip-on :noob:

I've had trouble finding anyone else with this same problem, but I'm hoping it a setting I've overlooked in TS. This problem is worst when shifting under high boost, theres a pretty significant lean spike that can last a good half a second in some cases. I've tried increasing AE, all it does is make it go even richer AFTER the spike. Its almost as if there is a significant lag coming from the AFR gauge. Additionally, the car will (sometimes) peg out lean but (always) fall on its face when you try to rev it from idle with anything but super gentle throttle applictaion (low tpsdot). I feel these two issues could be related. Datalog/Tune attached

I've tried:
-Increasing AE
-Richening lower right of VE table where shifting occurs
-using 25% mapdot instead of 100% TPSdot
-Changing the rpm range for AE

The car:
1990 miata with '96 1.8 swap
homeade log mani with ebay t3/t4
DIYPNP
1000cc deatchwerks
stock fp, fuel rail, etc
stock ignition
E85
1.8 vtps

Heres a screenshot of the lean spikes during an 1/8 mile pass
https://www.miataturbo.net/attachmen...ine=1444144173

Heres it coughing/falling on its face when tip in from idle
https://www.miataturbo.net/attachmen...ine=1444144173

https://www.miataturbo.net/attachmen...ine=1444147575


https://www.miataturbo.net/attachmen...ine=1444147575

So does this mean I need to mess with the rpm scaling moreso than the AE table? Rpm scaling reduces AE at high Rpms, so if I turn up AE to compensate, it will make off idle worse, correct?

on the first log it looks like your AE enrichments barely added any fuel, this made it spike lean. (spiking lean isn't so "bad" as long as you dont feel it).

the second log it looks like your AE enrichments DUMPED in fuel, and made the motor bog down, then it looks like you blew out spark or something.


what do your AE settings look like?

Increase AE at 770 tpsdot, decrease AE at 502 tps dot. Repeat. Hit those values at high rpm, hit those values at low rpm. Is the issue still there? Is the issue only at high rpms or low rpms? This is what data is for..

I cannot feel the lean spike while shifting, I was curious if it was dangerous or not. This hesitation happens at all tpsdot off idle. The only time you can really feel anything is when you are blipping the throttle at lower rpms (below 4500 or so). I've tried playing the AE values in the table quite a bit, maybe I just need to do it more. If a small lean spike during shifting isnt an issue, I suppose I could just tune it to feel right while hitting the throttle under no load.

https://www.miataturbo.net/attachmen...ine=1444151551

your TPS threshold is 300 %/sec...

your TPS log also shows it going into negative values. Unsure how one can achieve a -71% Throttle Position...

Ok, should I try raising it?

lol.

also what firmware are you using? I thought they got rid of "added ms" for "added %" like 5 years ago.

I'm fairly sure the DIYPNP is running 3.3.3. I believe this was the most up to date version when I put it together like 6 months ago. %/s would make things a lot easier. It looks like they've come out with 3.4.0 since then.

We've had issues with tps being noisy, going negative, etc. Didn't think it was really an issue as long as TPSdot works when you tip in

I'll go ahead and mess with tpsdot threshold since apparently it's way off (base map has 200%?). You sure don't want to make this easy

You want the tpsdot threshold as low as possible. As long as you don't get noise above the threshold. I think mine is around 5, if I remember correctly.

Thank you. It seems that's unrelated to the stumbling issue that happens above 300%/s

This is not a street car in any way, so I really don't care what it feels like at low tpsdot. Just trying to get it to rev up (usually 500%/s +) to the launch control limiter without it coughing


Edit: this is off the diyautotune site: "Note that MS3 has a slightly different PW adder - the MS3 uses a percentage of Required Fuel instead of an absolute number, making the AE stay the same when you change injectors. More about this later"

I have DIYPNP which is MS2...

I bet the VE table isn't tuned properly either.


You need to tune it in the higher load areas at idle speeds, (I drive around manipulating the throttle whilst left foot braking to keep the rpms low. if those aren't right you'll never get crisp throttle response off idle irrespective of what you do with AE

Did you calibrate the TPS?

TPS has been calibrated, although it has been awhile. I recall it was still occasionally giving negative values right after calibration.

It is possible to rotate the TPS to change the base numbers for open and closed.