Suburban update and a couple ??s

[1BadAction]

So I got down to the burb this weekend with a new ECM, and it started up and ran. With the Checksum disabled, I got a handle on it much quicker. Did a couple test drives in the neighborhood and have the "easy driving" fueling table in line nicely. At that point I started with the higher load lower RPM acceleration and was getting real bad knock counts AND audible knock, so I backed out of it and parked it. I mixed in fresh 93 octane a couple weeks back, but the fuel that was in it was mid grade when I parked it, so I'm thinking it's 89 octane, IF I'm lucky. I'll take 10 gallons of sunoco 110 with me next weekend and that should cure any knock issues with this load of gas.

Anyhow, one thing I would like to do is get this BAMT bin in to closed loop idle. I tried changing the MPH to enable open loop idle and the other parameter, and it didn't seem to work. How exactly do I enable closed loop idle with this bin? As soon as it goes into C/L it idles a good bit smoother, but it only lasts for 255 seconds after I put it into park, then it goes back into O/L.

[EagleMark]

There's still a lot of parameters missing from this XDF, like...

                    ;---------------------------------
                    ; IDLE  Cls Lp -> Opn LP 
                    ; TO STAY IN CLS LP, (IDLE)
                    ; o2 VDC MUST EXCEED THIS WINDOW
                    ;---------------------------------
L82DC   FCB  154    ; 757 Mv UPPER o2 THRESH
L82DD   FCB  69     ; 339 Mv LOWER o2 THRESH
                    ;---------------------------------
                    ; IDLE  Opn LP -> Cls Lp
                    ; TO GO CLS LP, (IDLE)
                    ; o2 VDC MUST EXCEED THIS WINDOW
                    ;---------------------------------
L82DE   FCB  157    ; 772 Mv UPPER o2 THRESH
L82DF   FCB  69     ; 339 Mv LOWER o2 THRESH
					;
                    ;-----------------------------

I'm not sure this is it? If this is commented correctly then not enough O2 swing?

Or is the O2 cooling off? Post a log of idle and it happening...

[Six_Shooter]

What code and ECM are you using?

[1BadAction]

$85 mask and 7060 ECM.

[Six_Shooter]

Hmm, I want to go the opposite way with a friend's '7060 application. I'll have a look into this a bit more.

[1BadAction]

There's still a lot of parameters missing from this XDF, like...

                    ;---------------------------------
                    ; IDLE  Cls Lp -> Opn LP 
                    ; TO STAY IN CLS LP, (IDLE)
                    ; o2 VDC MUST EXCEED THIS WINDOW
                    ;---------------------------------
L82DC   FCB  154    ; 757 Mv UPPER o2 THRESH
L82DD   FCB  69     ; 339 Mv LOWER o2 THRESH
                    ;---------------------------------
                    ; IDLE  Opn LP -> Cls Lp
                    ; TO GO CLS LP, (IDLE)
                    ; o2 VDC MUST EXCEED THIS WINDOW
                    ;---------------------------------
L82DE   FCB  157    ; 772 Mv UPPER o2 THRESH
L82DF   FCB  69     ; 339 Mv LOWER o2 THRESH
                    ;
                    ;-----------------------------

I'm not sure this is it? If this is commented correctly then not enough O2 swing?

Or is the O2 cooling off? Post a log of idle and it happening...

Mark, I'm not sure if it is commented correctly. I'm using the latest XDF you made with the mask ID. I'm still not sure on how the XDF works.

It's possible the O2 is cooling off, it's still a bit rich at idle and there is no cat, which I imagine helps hold heat in the upstream exhaust. I may end up going to Dallas for the weekend so I might not get to it this weekend but if I don't, I'll get to it next and post up a log.

[chevmasta]

Why is it knocking? too lean or too much spark or both?

My banc.bin doesn't go into O/L idle very easy. Does have the same 255 second counter though.

[1BadAction]

Why is it knocking? too lean or too much spark or both?

My banc.bin doesn't go into O/L idle very easy. Does have the same 255 second counter though.

Stale gas and 9.7:1 compression. It's on the stock timing table and in the section I'm getting knock it's only 13 degrees advanced.

I put 10 gallons of 93 in it but I don't think it was enough.

[EagleMark]

Stale gas nowadays usually means a puddle of water in bottom of tank as well... gotta love government putting ethanol in out gas tanks. Less emissions! Woo Hoo! And burn 10% more fuel to make same MPG...

[1BadAction]

Stale gas nowadays usually means a puddle of water in bottom of tank as well... gotta love government putting ethanol in out gas tanks. Less emissions! Woo Hoo! And burn 10% more fuel to make same MPG...

Yes, 2% less emissions and we use 10% more. Don't get me started on ethanol. See the boat in my signature? The bare hull is right at 500lbs, the engine is a nicasil bore EFI, 280hp at the propshaft and spins over 8500RPM. With all the humidity down here, the first thing that happens to an open to atmosphere fuel tank is condensation. Best thing to do is empty the fuel out every trip or you'll end up with rusted fuel pumps ($700 Weldon that's garbage, yay!) or worse yet a stuck fuel injector that wastes a $7,600 block.

At any rate, I'm going to siphon all the fuel out of it and throw 10 gallons of the good stuff in it. Can't mess with it this weekend because it's mothers day.

[EagleMark]

Can't you get non ethanol fuel down there for the boat?

Now that weather here has turned from nuclear winter to spring and a dam good one too, 70-80 for over a week! I'm back to MPG testing, so far it is worth the money for premium octane. Last year I did some quick tests with non ethanol and it to was cheaper with added MPG over 87 ethanol on freeway drives. Not sure it would be cheaper MPG in town driving though...

Non ethanol will always put out more WOT HP on dyno... boats have to change props from E fuel to non ethanol...

[1BadAction]

Can't you get non ethanol fuel down there for the boat?

Now that weather here has turned from nuclear winter to spring and a dam good one too, 70-80 for over a week! I'm back to MPG testing, so far it is worth the money for premium octane. Last year I did some quick tests with non ethanol and it to was cheaper with added MPG over 87 ethanol on freeway drives. Not sure it would be cheaper MPG in town driving though...

Non ethanol will always put out more WOT HP on dyno... boats have to change props from E fuel to non ethanol...

Yes we can get non-e but it's only 90 octane, which is a no-go. With 160psi of compression 93 is a must and even that makes me nervous. For as much as I use it, I've seriously considered cutting the heads and running leaded race fuel. Compression REALLY wakes up a 2 stroke.

Good to hear on the weather, it actually cooled down a bit here the last few days, been in the high 70s. I figure it's the last time we'll see lows below 70 degrees until fall comes around. Nothing quite like walking outside at midnight to 80 degrees and 95% humidity, lol. I've also found the same with fuel mileage in my GMC, a good hot tune with 93 octane always seems to get 2 or 3mpg better on the highway.

BTW> Looks like I missed a parameter when looking at closed loop idle.

[EagleMark]

That may be it! There's one similar in $42 for idle and the OL idle ones are set like yours/above. The CL idle bins are Idle Off 25. RPM and Idle Off 50 RPM.

There's must be a timer parameter as well, $42 has it, but if it never enters OL idle the timer won't matter.

[1BadAction]

Yes there is a timer parameter also. Mine is set to 255 seconds. I'll try 25 on and 50 off and post results. Right now it's idling dead smooth at 800rpm and 45/50kpa, it'll probably drop down to a solid 45 when I bump the idle down to 750.

[EagleMark]

Lowering idle will usually raise MAP. 800 is not high in a BB, there's usually 750 warmed up, if it's OK in gear and not pushing the brake to hard leave it... lower MAP at idle is always better. Sometimes 50 RPM and 5 degrees spark at idle with a cam makes a 10 MAP difference.