Good warm idle, but issues when cold, ASE, WUE

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deathtrapmiata
MS/Extra Newbie
Posts: 34
Joined: Mon Mar 24, 2014 12:39 pm

Good warm idle, but issues when cold, ASE, WUE

Post by deathtrapmiata »

1994 Mazda miata, (99' cylinder head and idle valve) 1.8l 4cyl...COP igniton, MSPNP gen 1,
42lb RX-8 Hi-imp injectors...naturally aspirated until my supercharger & meth-injection kit goes back on this weekend

...So for the first time in forever I finally have a good steady idle...but only when the car is perfectly warm
when warm* idle values are:
-900-1000 rpm - idle duty cycle @ 30%
-VE is at 37 - AFR: 13.2 - 14.0!!
- 8.0 req-fuel (425ccinjectors)
- pulse width: 1.8-2.0
- MAP:24-29 kPa

Air Fuel Ratio is around 13.3-14.0, very rich but if i take my idle VE cells
and cut every thing by -1 its in between 14.6-15.2....and it oscillates a bit more...good or bad? should i try to get it a little more lean?

Now the first start of the day is pretty rough, if im not blipping the throttle the second it starts to run, it dies.
also once I surpass that time period where I dont have to hold the throttle, it oscilates like crazy, until warm.

The second issue happens when I start the car again after its warm, but has been setting a few minutes
It cranks up just fine, but RPMs get low...like 700's-800's and the AFR gauge is crazy lean....I see AFR's of 17s, 18.0 + and it will go on for some time until i start to throttle it ...
2015-01-30_14.46.39.msl
zack'smiata.msq
please take a look at my tune and my data log
** the data log was taken after the car had been ran, but then set in the parking lot for about 3 hours... so CLT temps were 90* degrees
this data log does not reflect the SECOND issue that im talking about. just the cold/ warm up issues...i can post a second datalog If you would like to see that.
Matt Cramer
Super MS/Extra'er
Posts: 17507
Joined: Thu Apr 16, 2009 8:08 pm

Re: Good warm idle, but issues when cold, ASE, WUE

Post by Matt Cramer »

Are the temperature sensor readings accurate?

If so, it may just need some tweaks to the cranking pulse width and afterstart enrichment.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
deathtrapmiata
MS/Extra Newbie
Posts: 34
Joined: Mon Mar 24, 2014 12:39 pm

Re: Good warm idle, but issues when cold, ASE, WUE

Post by deathtrapmiata »

So from what I understand ASE is just added into warmup enrichment but only for the first ~30 seconds once the engine has started running.
- its strictly time based and only adds fuel related to that set time.

- from there on, its just warm-up enrichment when the car is idle (cold or CLT <160)
- until the throttle is moved, which then its using the VE table only?

When the car is still cold (CLT <160*) and I take off / drive anyways.. its pretty rich AFR's are like in the 12's

And I still just dont understand Cranking pulse widths... these are just extended fuel spraying times only while I'm starting the car?

SO, should I just add a few +1 or +2 to the ASE table values and a few 0.1's to the CPW's or do they need to stay linear to the base maps layout?
Matt Cramer
Super MS/Extra'er
Posts: 17507
Joined: Thu Apr 16, 2009 8:08 pm

Re: Good warm idle, but issues when cold, ASE, WUE

Post by Matt Cramer »

deathtrapmiata wrote:So from what I understand ASE is just added into warmup enrichment but only for the first ~30 seconds once the engine has started running.
- its strictly time based and only adds fuel related to that set time.

- from there on, its just warm-up enrichment when the car is idle (cold or CLT <160)
- until the throttle is moved, which then its using the VE table only?

When the car is still cold (CLT <160*) and I take off / drive anyways.. its pretty rich AFR's are like in the 12's

And I still just dont understand Cranking pulse widths... these are just extended fuel spraying times only while I'm starting the car?

SO, should I just add a few +1 or +2 to the ASE table values and a few 0.1's to the CPW's or do they need to stay linear to the base maps layout?
Not quite. The warmup enrichment is applied across the board until the temperature reaches the point on your WUE curve where you have 100% WUE.

MS1 cranking pulse widths are raw pulse widths used when RPM is below cranking RPM.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
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