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View Full Version : P0606 update-LBZ stalling-Fuel pressure anomolies



killerbee
July 21st, 2009, 12:18 AM
Sep thread, continued from another...I will supply updates on this problem as they arise. IMO, this is important, and a safety issue. The truck has stalled several times with the onset of the code. Someone will get hurt eventually if ignored, just a matter of time. The truck stops turning corners when the engine stops. :)

B1115 appears to set the code when values other than zero are entered at 0 TPS. Now before someone goes cracking wise, I suggest a new look.

There is some update to this as well. I played with B1102, 0 ft-lb values, and the same thing happened. NOW THIS IS NOT proof that these tables are causing the codes, but indicative. What was WORSE this time, is that fuel pressure went everywhere, uncontained. At or near idle, I saw 190 MPa, and some crazy detonation. Frankly, its a little scary.

FWIW. I don't think lip service is going to make this go away. IMHO, the cells need to be removed from the interface, or the bug needs to be investigated. I am assuming it is more universal than just a single vehicle.

Anyone playing with these cells need to be on a straight road when testing, I very nearly plowed into a family when the steering/brakes went out. :shock:

GMPX
July 21st, 2009, 09:11 AM
Michael, I can't remove select cells/rows because of the layout of the table in the ECM, either the table is there or it isn't. If it's as bad as you say then it will be removed from the software in the next release.

killerbee
July 21st, 2009, 09:54 AM
Yikes. If you remove both tables, there is nothing left to tune, no way to dose fuel. Maybe put a warning in the description?

GMC-2002-Dmax
July 21st, 2009, 10:27 AM
Michael, I can't remove select cells/rows because of the layout of the table in the ECM, either the table is there or it isn't. If it's as bad as you say then it will be removed from the software in the next release.

Please do not remove tables, especially that one.


Sep thread, continued from another...I will supply updates on this problem as they arise. IMO, this is important, and a safety issue. The truck has stalled several times with the onset of the code. Someone will get hurt eventually if ignored, just a matter of time. The truck stops turning corners when the engine stops. :)

B1115 appears to set the code when values other than zero are entered at 0 TPS. Now before someone goes cracking wise, I suggest a new look.

There is some update to this as well. I played with B1102, 0 ft-lb values, and the same thing happened. NOW THIS IS NOT proof that these tables are causing the codes, but indicative. What was WORSE this time, is that fuel pressure went everywhere, uncontained. At or near idle, I saw 190 MPa, and some crazy detonation. Frankly, its a little scary.

FWIW. I don't think lip service is going to make this go away. IMHO, the cells need to be removed from the interface, or the bug needs to be investigated. I am assuming it is more universal than just a single vehicle.

Anyone playing with these cells need to be on a straight road when testing, I very nearly plowed into a family when the steering/brakes went out. :shock:

Why would you put a fueling request in a row with 0 tps% ???? Are you kidding me ???

0% TPS is just that, 0% !!!!


Yikes. If you remove both tables, there is nothing left to tune, no way to dose fuel. Maybe put a warning in the description?

I have a better idea, leave it all ZERO's...............:shock:

killerbee
July 21st, 2009, 11:38 AM
Believe it or not, the truck uses fuel at 0% throttle.... and it is irrelevant. If YOU nearly went off the road in a stalled vehicle, you would be speaking for the next guy who could kill his family after changing those values.

So do me a favor, stop giving me lessons.

GMC-2002-Dmax
July 21st, 2009, 12:09 PM
Believe it or not, the truck uses fuel at 0% throttle.... and it is irrelevant. If YOU nearly went off the road in a stalled vehicle, you would be speaking for the next guy who could kill his family after changing those values.

So do me a favor, stop giving me lessons.

I am tryiing to offer you advice, maybe a tuning lesson at the same time for your own good.

I know that you might not like to hear it, but, on LB7/LLY calibrations you should look up table B0755 AND B0766, Look it up and see what it does. It may exist in LBZ/LMM's and Ross has not looked for it yet or feels it is not relevant yet.

I am wondering what you are trying to accomplish by altering that row of that table ??

I am sorry to hear you almost crashed a customer vehicle trying to tune it, but I still cannot fathom what you are trying to accomplish by changing the 0% TPS row in the tune file...........:confused: :confused: :confused:

In all Diesel calibrations that value in that row is ZERO........I am assuming for that reason........I have not ever made a change to that row.............:doh2:

killerbee
July 21st, 2009, 12:27 PM
I use it to remove the off-idle deadband. It's a refinement technique that gets rid of the "jerky" throttle response from interpolation. It's nice for the vehicle to respond before you get to 10%. ... all off topic.

...I can live without it, no worries...it would be nice, but this other issue is more important: keeping people on the road.

For me it was only embarrassing. The first time it stalled was after the customer took receipt. Imagine my relief and gratitude that I have the opportunity to correct it. Others may not be so lucky.

Ross, if there is anything I can help with, I have the vehicle back for a few more days. FWIW. I kept the logs of the anomolous behavior and stall. I realize this is a testy ECM, I have no suggestions, no expectations. Just feel it was important to bring proper light to something like this. I will sleep better.

killerbee
July 21st, 2009, 12:30 PM
update: so far no codes since zeroing out the 0 TPS row on both tables, 2 days, 10-20 miles

GMPX
July 21st, 2009, 12:32 PM
What about if we put a big warning in those tables? People don't want them removed, besides, many tables could potentially make the truck unsafe. True, this is a bit of an oddity as to why it happens, but it's not like the cause of it is not known (now).

bballer182
July 21st, 2009, 01:07 PM
Michael... In previous threads i have suggested the same. and in this instance it sounds like it would be an even bigger reason to not mess with the TQ tables. Not only does it cause what you have described it also alters the shifting patterns at well because you are requesting different amounts of TQ per TP and does not match or coincide with the TCM part throttle shifting tables.

So once again i'm going to suggest to you altering the TQ based fuel B1102 table NOT the B1115.


I'm going to have to side with everyone else. I would have never thought that anyone would have messed with that,... ever!

It's just like when a newbie takes B0728 in the LLY and maxes it out and starts it up for the first time and it idles OK then when he puts it in "D" it runs away because there is no constraint there...


Ross,
Maybe you are right.... A big huge red warning would be a good idea on those two table not to mess with the 0% TPS rows....

killerbee
July 22nd, 2009, 03:51 AM
This is going to be easier on me, if I could get treated like I didn't roll off the turnip truck. I'm not asking for much.


I'm going to have to side with everyone else. I would have never thought that anyone would have messed with that,... ever!

.

This chart is why I change the 0 TPS values: torque spikes (hence fuel spikes).

http://forum.efilive.com/attachment.php?attachmentid=5890&d=1248281399

The cursor is on it. To an OCD refinement niche specialist, this is most annoying, though I realize some of you don't wear balet slippers when driving your truck :) . Just tolerate me for a sec. Drive an LBZ or LMM, notice that every time you depress the acc, you get a brief period of....nothing...a latency hickup. This is what's happening.

The great part is,you can completely get rid of it by loading values in the 0 TPS row. The anomoly most certainly comes from the reality that the ECM is confused because it is commanding 120 ft-lb worth of fuel at 0 tps idle. As soon as you go to 1%, it gets confused because 0 torque (interpolated) fuel would not be enough fuel to keep it running. Each time you touch the throttle, this electronic confusion occurs. And BTW, it happens in all LLY's and LB7's as well, and I have tuned it out in each one, with no adverse side effects.

Maybe it can be addressed with an alternative method in the LBZ.

I realize we all tune to different goals. I would appreciate not be demeaned just because my goals are not similar to yours. Call it what you want, but you can take my 500 HP LLY and maneuver on an ice rink in 2wd without spinning anything. Right now, I can't do that with this test bed.

...and yes, I "understand it is a truck". Thanks in advance for the tip!!! :blahblah: If this doesn't generate enough interest on the benefits of solving the "0 tps" problem, then I have nothing to add.

killerbee
July 22nd, 2009, 07:04 AM
just curious, why are there 12 P0606 codes in C6001?

GMC-2002-Dmax
July 22nd, 2009, 08:37 AM
I am going to offer only my personal experiences, I have driven my 2002 LB7 for 7 years and over 130K miles, I never noticed a dead pedal.

I have a 2007b LBZ I drove stock, completely stock for a year, no dead pedal, I put a small stock tranny safe tune in, again no dead pedal, I have a big tune in it now, probably 450-500 hp, again no dead pedal.

I now have 32K miles on it.

I am not sure what you are experiencing from off-idle to say 30-50% TPS or even if you are creeping around at 10-15% TPS but whatever it is you are trying to get rid of I am just not feeling ????

But have at it if it bothers you .

:cucumber:

GMPX
July 22nd, 2009, 09:12 AM
just curious, why are there 12 P0606 codes in C6001?
Thanks for your other detailed post Michael. I think the approach I should take is to see if there is an additional dampening type table that might be causing you the problem given your current solution is too hit and miss (and dangerous).

On the multiple codes, well, what can I say, you often hear me say I don't like working with the Bosch ECM, there is another example as to why. The DTC processing is very convoluted, but, IMHO not as detailed as the LLY in processing faults. It took me a while to get my head around what they were doing and to be honest I'm not sure I still have it figured out 100% because I know in some instances you can turn a DTC off and it still shows up!
What it comes down to is they can assign a DTC number to numerous fault conditions. Eg, P0606 might come on due to a Flash Memory Error, or an A/D converter error, or they could even make it come on for a MAF error if they wanted to, it's all a bit of a mess and not specific like the Delphi ECM's are.

Cheers,
Ross

killerbee
July 22nd, 2009, 09:15 AM
Thanks!

bballer182
July 22nd, 2009, 11:42 AM
A couple of things that i see that a a little weird within this log.

According to RPM and TP there is 256 ft/lbs being requested. That's about 100 more than stock.

Fuel pressure is about 5-8 MPa more than stock at just about idle

Commanded fuel at the spike is a little over double where it should be.


If you look at B1102 there is a higher "resolution" of tuning there at the TP that you are looking at.

killerbee
July 25th, 2009, 04:25 AM
update: been running 2 days with torque values loaded in 600 and 800 rpm only, no codes.

This is enough to remove the anomolous off-idle torque spikes.

Cougar281
July 29th, 2009, 02:32 AM
For what little it's worth, I get a "dead pedal" reaction on my LLY from a stop for a fraction of a second, but only when running a DSP OS. I wonder if what you're trying to smooth out is what I'm getting. It's just odd that I only notice it in the DSP OSes.

killerbee
July 29th, 2009, 03:32 AM
For what little it's worth, I get a "dead pedal" reaction on my LLY from a stop for a fraction of a second, but only when running a DSP OS. I wonder if what you're trying to smooth out is what I'm getting. It's just odd that I only notice it in the DSP OSes.

put zeros in A0136 thru A0138

Cougar281
July 29th, 2009, 03:47 AM
put zeros in A0136 thru A0138

They are.... :confused:

killerbee
July 29th, 2009, 03:49 AM
that was an issue for me. Sorry