7427 install, first impressions

[JeepsAndGuns]

The 7427 I have was stock with the BJYK BCC, witch is a 0D mask. And like mentioned, I am using a tuned BMHK bin witch is 0E. I am having no pcm problems.
How come there is 0E and 31 masks if they both seem to be for the same applacation (HD truck/van with 4L80E) Why make two masks, who not just use the same one? GM is odd sometimes.
I downloaded the 31 mask from TP so I could look at these bins. But it appears 0E and 31 both use the same datastream defination. Making things more confusing on why is there even a $31 mask?

[Six_Shooter]

I have 2 $31 .XDFs in my folder.

One is probably very incomplete though, it's only 70Kb in size, while the other is 1161 Kb in size. lol

[Six_Shooter]

Let's try this...

[EagleMark]

Thanks Chris!

Got some info on throttle Kickers!!! They were for soliniods and the govener paremeters... topic still underway here.
http://www.fullsizechevy.com/forum/gene ... ost5437704

[attachment=0:1bunschm]TBI-Kicker_govener.jpg[/attachment:1bunschm]

[JeepsAndGuns]

Very interesting. I have never seen a tbi unit that looked like that.
In the bin I am using, it has a tempature to enable throttle kicker. Cant remember the exact temp without looking, but I know it doesnt enable untill the engine warms up just a tad, so when its still cold, it will do the slight/momentairy stumble as I am pulling out. Once it warms up some and the TK enables, I can pull out with no stumble, it just goes.
Well, come to think of it, I dont really have any FIRM proof that it is in fact the throttle kicker feature, it could be some other setting in the bin I know nothing about. But I do know when I disabled the TK, it would do it every time I pulled out, and with it enabled, I pull out no problems. I will keep an eye on that thread.

[EagleMark]

Well one guy said yes it is IAC logic and that would corespond to what your saying.

The other guy said it's to control Kicker along with govenor shown in picture, but has not said it has nothing to do with other IAC logic...

So maybe it is both. Wonder if it shows in $OE as that seems to be for Auto and light duty?

I have seen that TBI without big bulk on side. It was on a 366 Chevy truck motor. It has the big bores but smaller injectors with uiuque injectors. They are used on commercail trucks. The one above has the throttle Kicker to raise idle when something like a PTO, welder, airpupmp is turned on.

[EagleMark]

I had to EDIT one of my earlier posts to make info correct. It states:

EDIT: In looking at $OE it does have bins and paremeters for manual trans and controls and Auto 4l80E and 700R4. But does not have 4L60E.

[gregs78cam]

It seems to me that when GM started putting the 60E and 80E in they still had some applications with manuals and some with TH400. So they needed PCMs with different abilities in the beginning. Then eventually they superceded the '8625, '7060, '6395 with the '7427 that running $0D or $0E could handle everything and backwards compatible to run the same masks as the old ones. Just my thoughts.

[EagleMark]

That actually makes sense if you look at the years of the PCMs!

[JeepsAndGuns]

Does seem to make sense.

Heres something new that has started since I have gotten the speed sensor working with the 7427.
When driving along steady and you hold the pedal at the "in between" point, to where you are not accelerating or decelarating, kinda at that point right before you would be in decel, it wants to kinda sputter/miss. I dont know if its really missing, but it just kinda sounds like it. No backfires or anything, you can just feel/hear it in the engine, and its only mild, but enough to be annoying and make you notice that something not quite right. I kinda almost want to discribe it as its like the engine is trying to figure out if it should be in accel or decel. It kinda wants to do it a little more noticeable when its still warming up, and not quite as bad once its fully warmed up, but still does it when warm.
Any ideas on what it might be and what I might try to correct it?

[EagleMark]

Depends on what TPS %? Sounds like your almost trying to find DFCO...

[JeepsAndGuns]

I thinking its something the pcm is trying to figure out.
I'll have to do a datalog and see if its at a specific tps, and see what other things are going on when it does it.

[Six_Shooter]

I would look at timing. I was able to clear up a lot of that low load surge in a few cars by adjusting timing. Depending on the car more timing helped, in others, reducing timing helped.

[EagleMark]

I hear what your saying but from what he is describing is not low load, it's no load, almost like idle when cruising...

Jeeps and Guns, does it do it if you let throttle completly off? Or just when your trying to find differance between accelerate and decelerate? Or is Six Shooter right and low load (accelerate)?

[Six_Shooter]

I hear what your saying but from what he is describing is not low load, it's no load, almost like idle when cruising...

Jeeps and Guns, does it do it if you let throttle completly off? Or just when your trying to find differance between accelerate and decelerate? Or is Six Shooter right and low load (accelerate)?

It would be considered low load. "load" does not always mean acceleration, it just means a load on the motor other than to keep itself running, which could also be considered a load, depending on how you look at it.