Chevy's Dreaded Displacement on Demand bit my Silverado last week

[Sigblitz]

.Ford had a very interesting version of4 DOD by blowing out sparkplugs when they weren't needed.

Yes the bigger motor, 4.8 I think, not enough threads. Antiseize and 25fp.

 

[printcraft]

Speaking of checking your oil... Search for the 'I do cars' channel on YT. You'll see what oil starvation looks like/results in.

Just make sure to refine your search a bit...

 

[Cozy439]

My first car was a '73 Pontiac Ventura. Piece of garbage, but I could fix it it cheap and easy, if I needed to. I never did, just sold it to the scrap yard when I was tired of it.

2nd car was a 1966 Impala survivor. I did work on that, and it was simple, cheap, and easy. Raise the hood, so much room under there, get your work done and get back on the road.

3rd car was a restored 1966 Impala. Gorgeous car. Lost the mechanical fuel pump somewhere around Elizabethtown KY. Long story short, hitched a ride to E-town, got the part, replaced the fuel pump at the side of the road and it lasted for years until I sold her.

Since then, it's been up and down. Mostly down. Cars have gotten smaller, which means less room under the hood, and they're not designed with maintenance in mind. You have to be a contortionist to work on newer vehicles, and sometimes you have to pull the pack to get to the basic parts.

The US government did this to us. They set out to kill the shadetree mechanic, and they did that.

Some of you may have read about the death of my '06 Pathfinder. I really wanted to get an old school, air-breathing, classic piece of Detroit metal. But I'm too old for that now. Got a modern car with a warranty. Can't imagine having to pull the pack to change the oil pan if I hit some road debris, or reprogam a computer when it goes all HAL 9000.

My 1st car was a '67 Impala - SO TRUE about the room under the hood. No AC, no power anything, no electronics, ect to get in the way. Just a 427 V8. So easy to work on

 

[BehindBlueI's]

Who has the tuner to get rid of it on a 15 and up?

Tow haul mode changes all the shift points. I do the manual select of gears but it's a pain. I want it gone so that if someone else drives it they don't have to do the hokie pokie button dance.

hemifever@hemifevertuning.com does custom tunes but you'll need an unlocked PCM. I think they will also do that for you.

 

[Jaybird1980]

hemifever@hemifevertuning.com does custom tunes but you'll need an unlocked PCM. I think they will also do that for you.

I'll have to check it out. I haven't seen one that is tune only.

 

[HoughMade]

So...in what I hope is the final chapter of the Displacement on Demand saga....emissions testing. My son has put several hundred miles on the truck since the repair. No problems whatsoever...but just because there is no "Check Engine" light doesn't mean you pass emissions.

Those of you who live in most of Indiana, where freedom reigns, you don't have to get your vehicles emissions tested.

However, those of us in "The Region" have to get our cars tested every other year. In a relatively modern car (OBD II), this means hooking up to the OBD port and making sure no codes are set...AND that all of the on-board monitors have gone through their cycles and self-tests. No tailpipe sniffing.

Therein was the problem. The "Check Engine" light was not on, but the little device I plugged in to keep the DoD from going into V4 mode also fooled the engine in such a way that it did not record going through all of the on-board diagnostic monitors. Therefore, I could not pass the testing even with no light on. I have a code reader that will give me monitor status and it had not completed a few of the monitors after about 650 miles. Usually 2 or 3 days of driving will do it.

Now, earlier in the thread, you may see that I modified the VLOM so it cannot physically activate the V4 lifters and get stuck again. However, without the "reprogram", the injectors on the V4 cylinders will be deactivated when it signals to go into V4 mode and I will get rampant misfires, lighting the CEL and not passing emissions.

After researching, I found out that the Displacement on Demand parameters include being in a gear over 3rd gear and speeds over 55 mph. I figured out that if I drove around in 3rd gear, never getting into overdrive, I could still drive the speeds required (30-60 mph) and complete all of the parameters for the on-board diagnostics to do their voo doo without Displacement on Demand being triggered.

Anyhoo, I completed the 3rd gear drive cycle this morning and my son got it tested this morning. Pass. Now, we plug the "reprogrammer" back in and go on with life, able to use 4th gear again.

We are hoping to sell this in another month or 2. The truck runs and drives great...but would be at its best in counties other than Porter or Lake.

 

[actaeon277]

So...in what I hope is the final chapter of the Displacement on Demand saga....emissions testing. My son has put several hundred miles on the truck since the repair. No problems whatsoever...but just because there is no "Check Engine" light doesn't mean you pass emissions.

Those of you who live in most of Indiana, where freedom reigns, you don't have to get your vehicles emissions tested.

However, those of us in "The Region" have to get our cars tested every other year. In a relatively modern car (OBD II), this means hooking up to the OBD port and making sure no codes are set...AND that all of the on-board monitors have gone through their cycles and self-tests. No tailpipe sniffing.

Therein was the problem. The "Check Engine" light was not on, but the little device I plugged in to keep the DoD from going into V4 mode also fooled the engine in such a way that it did not record going through all of the on-board diagnostic monitors. Therefore, I could not pass the testing even with no light on. I have a code reader that will give me monitor status and it had not completed a few of the monitors after about 650 miles. Usually 2 or 3 days of driving will do it.

Now, earlier in the thread, you may see that I modified the VLOM so it cannot physically activate the V4 lifters and get stuck again. However, without the "reprogram", the injectors on the V4 cylinders will be deactivated when it signals to go into V4 mode and I will get rampant misfires, lighting the CEL and not passing emissions.

After researching, I found out that the Displacement on Demand parameters include being in a gear over 3rd gear and speeds over 55 mph. I figured out that if I drove around in 3rd gear, never getting into overdrive, I could still drive the speeds required (30-60 mph) and complete all of the parameters for the on-board diagnostics to do their voo doo without Displacement on Demand being triggered.

Anyhoo, I completed the 3rd gear drive cycle this morning and my son got it tested this morning. Pass. Now, we plug the "reprogrammer" back in and go on with life, able to use 4th gear again.

We are hoping to sell this in another month or 2. The truck runs and drives great...but would be at its best in counties other than Porter or Lake.

Some cars have very simple steps for the computer to show 'okay'.
Drive for so many miles, or for so many hours.

My 2009 Ford Escape has a page long criteria.
The warm up
The highway drive
The city drive

And each of those has parameters you have to meet.
Change the battery in your vehicle, need to go through the checklist again.
I found out after around a year, that I had not completed all the checks, so couldn't pass emissions.

Went online to download the profile.
After 3-11s, I completed the entire profile on the way home, twice.
I had to do it in the evening, because during the day I'd have a hard time being in parameters. Too fast or Too slow.

 

[jamil]

When they plug in upon inspection, it should just say, **** you, none of your business.