Accel Enrichment / Stall issues (90-93 DIYPnP)
 

Hey there!

I got the MS running perfectly, the car is idling pretty fine, and the VE table needs some adjustment but otherwise they're good enough to perform some running tests...

Now I have a slight issue. I tee'd a pipe off the FPR and into the cabin for the MAP sensor, and even so I still don't get a proper throttle response. When I press the pedal, even if it's ever so slightly, the car stalls for a fraction of a second and then revs. I'm pretty positive this is the Accel Enrichment acting up, because the AFR on the wideband shows me a very very lean mixture the moment I press the gas pedal. MAPdot wasn't set, so I set it (previous owner had TPS and I missed this bit) and that didn't solve me problem either.

Here's the settings I'm using:
https://www.miataturbo.net/attachmen...ine=1335887083
https://www.miataturbo.net/attachmen...ine=1335887083
https://www.miataturbo.net/attachmen...ine=1335887083

Remember this is a '91 Miata running a 90-93 DIYPNP, aspirated, with no TPS or AFM. All stock except cone filter and cat-back stainless exhaust. Also, using a sealed element sensor for IAT.

Can it be that the pipes for the MAP are too flexible or something?

blip throttle, watch it move on that slider up. add "value (ms)" in places within the rate shown.

Oh man, this worked like a charm! I settled at about 6ms/9ms/12ms/15ms (respectively, from the bottom up) and the car does not stall anymore! It's almost as good as stock!

Man, I'm so happy if you were a cute gal I'd kiss you :giggle:

Thanks so much Brain!

Brain, what is the equivalent of this slider on Tunerstudio?
I don't recall seeing one. Is it more of test-and-feel type for TS users then?

Of course, I do not have the laptop with TS with me today to check.

TS uses a curve, and there's a green dot that rides on teh rail. like monorail cat.

So I noticed on mine it never makes it very far up the curve does that mean I need to reset the [arameters using the grey dotted box in top right corner of each graph to make a better map for my setup.

I am totaly lost in tunnng enrichment.

Are you looking at the curve while in neutral free reving? Ooor in gear under load?

the curve is the rate you slam the pedal, if you are never able to get it to scale up the curve, maybe you need to reduce the rate values so you can fine tune the curve.

Ok that makes sense.
Just so I understand.
move dot up more fuel move dot down less.
How do I tell which to do. Is it based on afr? or Feel of the engine?

My accell enrichment sucks.

You choose whether you want to make the enrichment MAPdot or TPSdot based, and also if you want RPM based enrichment to go with either. AFR is of no importance as far as configuration goes, except you'll want to check whether you're too lean or too rich on acceleration.

For mine (no TPS) I chose MAPdot with no RPM accel enrichment, and used the values I provided above. It still gets a bit on the rich side when I press the pedal, but it's hardly noticeable while driving, and when the car is warm. When the car is cold, I stil get a bit of a lean spot when the car is cold (right after start).

You can see all of my settings above, they change a bit on the Accel Enrichment Wizard if you're using TunerStudio, but they're pretty straight forward. Even if they don't suit your car, they might be a good starting point ;)

Pretty much. you're adding in extra fuel based of a %/sec rate change in MAP or TPS.

the value you are entering is litterally how much extra pulse width to inject.

the rate value is a % change / sec.

ideally you'd tune it so when you hit the gas off idle, or between shifts, you have plenty of fuel for smooth engagement...otherwise you'll have lean spikes and youll feel the car hesistate.

you'll tune off a curve where heavier inputs may need more fuel, and just little blips not so much. make sure you outer extreme rate isn't so far off the scale that you'll never move the throttle fast enough to hit that area, it's a waste of resolution.



I'd rather spike rich than lean, try to target the 14:1 area if you can.

increase the cold accel multipler to maybe 110% if you need a little more enrichments in the cold.