0411 PCM usage Dave W. please comment

[rsicard]

I'm not pissed off, I am busy person. I hold down a full time job, and operate a small EFi business. I enjoy helping others, but my employer / customers are a higher priority. I've considered upgrading my 93 K1500 to a 5.3 LS engine, mostly to increase my custom LSx wiring harness business.

For budget reasons, I would use the 2002 Express Van Vortec '0411 system on a SBC. I would avoid Drive by Wire. Everything for OBD2 tuning is expensive!

Troubleshooting is not easy. Troubleshooting over a keyboard can be very challenging! I don't like seeing someone waste time and money when troubleshooting. With an engine that is 100% original and 100% completely stock, troubleshooting strictly by the technical book is helpful. When an engine is not 100% original and not 100% stock, the individual doing the troubleshooting will usually require more troubleshooting experience than the technical book typically offer. Myself and other members here at gearhead-efi.com often share troubleshooting experience to other members.

It seems to me, you have more than one thing not 100% correct. I would focus on one problem at a time. I would configure the ESC (Knock System) to 100% factory stock wiring and parts. Usually having things configured like it was when it left the factory is a good plan.

dave w

Not sure why the negative comments about Drive By Wire. Understand need for compatible components configurations. Been in Aerospace Electronics for 38+ years.b As long as the software is robust, it should be safe. Need to invest in Megasquirt stimulator and make generic interface for testing OBDI, OBDII and others. Then be able to characterize the different PCMs and gain in depth knowledge about their operations and how to manipulate the binaries to attain desired results. Really like Electromotive PCMs at they are straight forward but lack trans control which is needed. Please advise. Thanks.

[fastacton]

Drive by wire is plenty safe and reliable, but it's normally not tuned for performance and it adds some expensive components with no performance gains. The manufacturers purposely take out some of the sensitivity and responsiveness in DBW in the name of safety, longevity and liability. In addition to the added expense of the pedal and module, the throttle body gets VERY expensive if you want to upgrade from stock. And you now have one more system to tune. For these reasons performance & budget minded people stay away from DBW.

[rsicard]

Drive by wire is plenty safe and reliable, but it's normally not tuned for performance and it adds some expensive components with no performance gains. The manufacturers purposely take out some of the sensitivity and responsiveness in DBW in the name of safety, longevity and liability. In addition to the added expense of the pedal and module, the throttle body gets VERY expensive if you want to upgrade from stock. And you now have one more system to tune. For these reasons performance & budget minded people stay away from DBW.

Thanks for chiming in. Understand exactly what you are saying which is appropriate. In terms of safety, likely GM added delay to responsiveness for driveability concerns, not performance. The TAC module may insert delay. As far as longevity, (dual) potentiometers tend to wear out. As far as liability is concerned, it is the Japanese that had the so called stuck pedal issue, i.e. unsafe DBW design likely fixed with discrete brake pedal input to halt uncontrolled accel. They designed themselves into an unsafe corner. And, DBW throttle bodies are expensive. Perhaps someone will come along and use a rotary encoder and happy box to output CAN data, directly to 0411 PCM, and eliminate TAC module. This function is now incorporated in the newer PCMs.

[fastacton]

As far as the stuck pedal issue goes, most of these were either a floor mat that came out of place, poor pedal size/placement or just driver error. I don't think there have been any safety issues with DBW that have been verified. This was mostly just a result of lazy media reports, just like the earlier Audi issue.

[rsicard]

As far as the stuck pedal issue goes, most of these were either a floor mat that came out of place, poor pedal size/placement or just driver error. I don't think there have been any safety issues with DBW that have been verified. This was mostly just a result of lazy media reports, just like the earlier Audi issue.

The floor mat issue likely was a red herring. People have been killed by Japanese DBW stuck throttle. The issue has been swept under the rug. The fixes (likely embedded software) were implemented under cover during routine maintenance on the affected vehicles. So far as I know, GM did or does not have this problem.

[fastacton]

Everything I've read points to overreaction by the media. From the NHTSA report:

NASA engineers found no electronic flaws in Toyota vehicles capable of producing the large throttle openings required to create dangerous high-speed unintended acceleration incidents. The two mechanical safety defects identified by NHTSA more than a year ago – “sticking” accelerator pedals and a design flaw that enabled accelerator pedals to become trapped by floor mats – remain the only known causes for these kinds of unsafe unintended acceleration incidents. Toyota has recalled nearly 8 million vehicles in the United States for these two defects.

[rsicard]

Everything I've read points to overreaction by the media. From the NHTSA report:

NASA engineers found no electronic flaws in Toyota vehicles capable of producing the large throttle openings required to create dangerous high-speed unintended acceleration incidents. The two mechanical safety defects identified by NHTSA more than a year ago – “sticking” accelerator pedals and a design flaw that enabled accelerator pedals to become trapped by floor mats – remain the only known causes for these kinds of unsafe unintended acceleration incidents. Toyota has recalled nearly 8 million vehicles in the United States for these two defects.

Did a lookup of the Toyota issue. Found the following from embedded.com. "The first thing you will notice if you join me in trying to judge the technical issues for yourself are the redactions: pages and pages of them. In parts and entirely for unexplained reasons, this report on automotive electronics reads like the public version of a CIA training manual. I've observed that approximately 193 of the 1,061 pages released so far feature some level of redaction (via black boxes, which obscure from a single number, word, or phrase to a full table, page, or section). The redactions are at their worst in NASA's Appendix A, which describes NASA's review of Toyota's embedded software in detail.¹ More than half of all the pages with redactions (including the vast majority of fully redacted tables, pages, and sections) are in that Appendix."

Hmm, wonder why all the redactions. Something smells a little fishy. Knowing the Japanese, they must not LOSE FACE.

[fastacton]

Without seeing the context of all of the redactions, we can only guess. My guess is that the report contains proprietary data that Toyota shared for the investigation but not for public release. I did review one of the NASA documents and the redactions I saw did seem limited to technical specifications of the system, which should be expected. A report like this is available to those that need to know and the whole document has to make sense before it's finalized. It's always possible that there's a conspiracy here, but that's not high up on my list of possibilities. I think an issue like this had enough personnel involved in the investigation, that it would be hard to keep it entirely under wraps. Toyota did lose face on this issue, they were at fault for their poorly designed floor mats and poor pedal placement and probably other things. Along with the desire to not lose face also comes the desire to be honorable.

[Lextech]

The original case of the stuck accelerator was a floor mat set installed into a model of car it was not designed for. That gas pedal got hung up and people died---Very tragic. Toyota/Lexus came out with a reflash that would cut the throttle input when the brake pedal is applied. To the best of my knowledge there were never any proven cases of unintended acceleration. Didn't anyone find it strange that out of the blue all of these cars supposedly had unintended acceleration and just as suddenly the complaints stopped. Very similar to a politician that has a flawless career then two weeks before an election multiple people accuse him of being a rapist or child molester.

Jeff

[fastacton]

The lawyers and media smell blood and jump all over that kind of stuff. Once they're proven wrong, you just never hear anything about it again. No apologies to the people or companies they've ruined.