New Tuning Tutorial: WeathermanShawn

[mr.prick]

Where did you find that ? I just checked OS 19980400 (that's the one I asked for) and a quick check of OS 19980200 and they are both X out as not valid. Is there something else I need to look at? Do I need to re-validate PIDs?

Thanks.

Sometimes PIDs are invalid until you start logging or monitoring.
Select them anyways and start logging/monitoring to see if they become valid.
Of course calc_pids need their dependent PIDs selected to be available.

[joecar]

...

if your OS doesn't have DYNAIRTMP_DMA, then you can approximate it using 0.85*ECT+0.15*IAT or by looking up the temperature blend table.

Joe, what's the basis for this estimator?

...

How close is that formula to the pid? Can someone do a quick comparison between the two and see how close the net values are?

It was late last night when I typed that... <- me slapping upside my head 4x

Sorry, I had meant to type this: 0.85*IAT+0.15*ECT

i.e. it should biased toward IAT.

I intended that as a simple estimation, exactly what Shawn guessed I was doing...

I say this from looking at B4901 and from observing DYNAIRTMP_DMA say when VSS > 30 mph in various logs...
I should have instead said to study B4901 for your airflow range, which brings us to the next point:

A more accurate way to do this is to do a lookup of the B4901 values as suggested by mr.prick earlier in this thread...
and this is exactly what Ninety8C5 did: showpost.php?p=118165&postcount=29

[ but this still doesn't factor in B4902 ]

[joecar]

Where did you find that ? I just checked OS 19980400 (that's the one I asked for) and a quick check of OS 19980200 and they are both X out as not valid. Is there something else I need to look at? Do I need to re-validate PIDs?

Thanks.

I see you have already found this: showthread.php?t=13320

Hmmm... I though I had seen an update for 19980200......I don't know now what I had been looking at (sorry).

Do what mr.prick said, Validate Pids.

[joecar]

Ok, I'm confused... I pm'd Tech Support regarding the 19980x00 os's support of these pids:

GM.CYLAIR_DMA
GM.DYNCYLAIR_DMA
GM.DYNAIRTMP_DMA

If DYNAIRTMP_DMA isn't supported, then the lookup of B4901 would be the way to go.

[DrkPhx]

Ok, I'm confused... I pm'd Tech Support regarding the 19980x00 os's support of these pids:

GM.CYLAIR_DMA
GM.DYNCYLAIR_DMA
GM.DYNAIRTMP_DMA

If DYNAIRTMP_DMA isn't supported, then the lookup of B4901 would be the way to go.

Joecar - Any updates on this?

BTW - Both GM.CYLAIR_DMA and GM.DYNCYLAIR_DMA work fine for me, it's just the GM.DYNAIRTMP_DMA that doesn't work.

[joecar]

Ok, I'm told that those do not exist for the 1998 OS's... sorry.

So the next best thing is to use the lookup(B4901) method, see Ninety8C5's link in my post above (post #162).

[Ninety8C5]

It was late last night when I typed that... <- me slapping upside my head 4x

Sorry, I had meant to type this: 0.85*IAT+0.15*ECT

i.e. it should biased toward IAT.

I intended that as a simple estimation, exactly what Shawn guessed I was doing...

I say this from looking at B4901 and from observing DYNAIRTMP_DMA say when VSS > 30 mph in various logs...
I should have instead said to study B4901 for your airflow range, which brings us to the next point:

A more accurate way to do this is to do a lookup of the B4901 values as suggested by mr.prick earlier in this thread...
and this is exactly what Ninety8C5 did: showpost.php?p=118165&postcount=29

[ but this still doesn't factor in B4902 ]

The 1998 OS's don't have B4902.

[joecar]

The 1998 OS's don't have B4902.

That's one less thing to worry about...

I think the lookup of B4901 will work pretty good (GM did spend many man-hours on this).

[joecar]

Here is the current calc_pids.txt file for the tutorial (works for VE[%] and VE[g*K/kPa]).


The pdf is included in the latest install of V7.5.

[stigmundfreud]

cheers Joe! I saw that thread the other day but didnt think it applicable due to e38 but if it does the MAF its worth a shot

PS do you not know where anythings located