P0606 update-LBZ stalling-Fuel pressure anomolies

[killerbee]

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.

[GMPX]

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]

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]

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.

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...............

[killerbee]

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]

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...........

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.............

[killerbee]

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]

update: so far no codes since zeroing out the 0 TPS row on both tables, 2 days, 10-20 miles

[GMPX]

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]

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....