cylinder airmass

[kwiktsi]

I am tuning my 01 camaro with a TSP Torquer v4, TEA stage 2 ls6 heads, bosch 36 injectors(fast), headers, etc.. I am doing the usual OLSD tune to get my VE dialed in and then running the maf to get that dialed in. I have noticed that while my final AFR is good on both tunes, my g/cyl readings are much higher with the maf hooked up than in SD. Is this normal or should I be looking for a problem somewhere? Also, my maf reading is pretty erratic. Am I better off just tuning SD with my setup?

I will attach the current tune and a couple of older logs to show the g/cyl difference between sd and maf. Thanks.
Joe

ps- 1.hpl is the sd log

[kwiktsi]

Anyone?

[mowton]

Log dynamic air as well as maf. They should be pretty close during steady state driving. Yes, the g/cyl should be close as well. If you maf is off than that might be an indicator. Make sure you are really in maf only and VE only when tuning each respectively. Post both ve and maf tunes as well as corresponding logs.

Ed M

[mowton]

The most obvious find is the MAF file needs to have the High RPM Disable set to 400 for MAF only tuning. That may bring the dynamic Airmass (PCM uses this to access spark table) in line with the calculated airmass (MAF developed)

Also PE enrichment s/b 1.13 across the board.

Spark table could use some work as well.

There is a large difference in the MAF AFR and SD AFR. While the MAF is a bit Rich, The VE is very rich at like 10.5/9sh. That will skew the SD load calculations. Looks like you just need to to fix the High RPM Disable in the MAF tune and work the SD tune to get closer to the Commanded AFR. Maf could use a bit of correcting as well.

Ed M

[kwiktsi]

I did realize after reading your post that I incorrectly did the maf tune. I just did my SD, then plugged the maf back in and tweaked the variances from there. Funny thing is with the maf hooked up or disconnected, I was getting 12.6 pretty much the entire wot pull aside from initial hit until things leveled off. My ve was set using a wideband at cruise and wot with the maf failed and unplugged and very minimal afr error. That's what's confusing me, I wasn't seeing any afr errors, just a big diff in cyl airmass with the maf hooked up or not.

I'll have to look at the timing tables on those files, I have tweaked them a bit since then. What stood out to you with the timing?

edit- now that I am looking at those logs, I am confused as to what was going on. I had posted this a couple of weeks back with no response and just bumped it, so my memory of it isn't that fresh . I have recent logs with a dead solid 12.6 afr through the whole pull, so I'm wondering if I screwed up and posted the wrong ones at the time. I do recall that I have my ve WOT a tad richer than my MAF AFR, I did this thinking just in case the MAF failed, I knew it would be safe? Sorry, my memory isn't what it once was with this stuff, I have way too many other things on my plate that take up valuable memory space haha. Let me see if I can find more recent stuff.

[kwiktsi]

Oh, and I have my pe set purposely at 12.6, wanted a bit of a safety net, especially while messing with the tune.

[kwiktsi]

OK, I apologize for any confusion, just looking over my current tune- I cleaned up the spark quite a bit and my PE is commanding 12.5 the whole way and IIRC was a dead straight line the entire pull now. Just need to see if I can find which logs it was. I'm almost wondering if I posted the wrong logs initially. I have hundreds and trying to do this in between a crying baby and my wife asking me to hurry up, I tend to lose track of what I am doing .

Here is the last log I did before pulling the wideband and my current tune. I had the PE set to 12.5 and it was close enough that I was happy with it when done. The timing in the latest tune has been dropped since the log due to some kr here and there. I pulled it down and will be slowly working it back up. I will be putting the wideband back in next time out to see what it's reading now. I'll also redo the maf only tune using your advice above. Thanks.
Joe

[mowton]

OK, I apologize for any confusion, just looking over my current tune- I cleaned up the spark quite a bit and my PE is commanding 12.5 the whole way and IIRC was a dead straight line the entire pull now. Just need to see if I can find which logs it was. I'm almost wondering if I posted the wrong logs initially. I have hundreds and trying to do this in between a crying baby and my wife asking me to hurry up, I tend to lose track of what I am doing .

Here is the last log I did before pulling the wideband and my current tune. I had the PE set to 12.5 and it was close enough that I was happy with it when done. The timing in the latest tune has been dropped since the log due to some kr here and there. I pulled it down and will be slowly working it back up. I will be putting the wideband back in next time out to see what it's reading now. I'll also redo the maf only tune using your advice above. Thanks.
Joe

Joe,

Looks pretty good. IPW is within margins and This log had a WB in it and it looked good as well. I updated you .cfg with Dynamic Air and the AFR error stuff. see if you like it.

Ed M

Default Imperialwideband rev a.cfg

[kwiktsi]

Thanks. Hopefully I'll get out at some point this weekend to do some more tweaking. The car has been serving dd duty without a hiccup, but always room for improvement . I'll give that configuration a shot. Thanks again!

[kwiktsi]

Well, still haven't gotten a chance to do any more tuning or logging. My laptop screen hinge broke and ripped the wires off the screen too. Fun.. Hopefully soon.

I did have another issue today, took it to bring my son to the bus stop a block away, so it never really got a chance to warm up. Shut it off for a few and when I restarted it, it kept wanting to stall, smelled rich as hell, etc. I had to keep it running for a little bit with the throttle and it was fine. I did the idle airflow logs and tables multiple times and they are fine. It has never done this if I let it fully warm up and shut it off/restart it all day with the exception of a slight idle drop on a hot restart with the ac on until it catches itself.

Aside from basic ve, timing, idle airflow, etc., I don't know a lot of what can be altered. Is there maybe a temperature based enrichment table that is too rich in that range? Thanks.

[mowton]

RussK-Idle-Airflow metric.cfg

Wondering if you have perfromed what is called the RussK idle air log? Attached is the .cfg to perform this. It is done from a cold start and you just let the car idle from cold to about 210-220 F or as high it will go. It is a good idea to shut off the fans during this test through the VCM controls. You do this in all 4 conditions...P/N AC off, In Gear AC off, P/N AC on and In Gear AC on. Takes a while but gets your idle in pretty ggod shape and sets a base line for your rolling idle...

Ed M

[kwiktsi]

I have done that a bunch of times and it is to the point where there is very little to no variance. However, I only did it in park and neutral, ac off. I under the impression that I should not do it with the ac on as there were other modifiers for ac compensation?

I did try bumping the idle airflow up a bit to see if it helped any and it did for a bit, until the ltit's compensated and put it back to how it was anyway. Thanks.
Joe

[mowton]

look at Engine>Fuel>General>Afterstart Enrichment

True, dont have AC adjustments rather offsets are stored in the PCM. As belt and suspenders during my idle process, I usually monitor AC on/off and idle effects and make tweaks to the AC torque and/or spark to settle it out if needed. You dont have to do that if you are idling OK with the AC on.

Ed M