He has a Monte. If I remember correctly, the Chevy twins have an indicator that tells which DOD mode they are in.

Chip

 

I thought I had read that somewhere, but wasn't sure if it was true. Would be nice if we also had one also. Ive been thinking about rigging one up. Wouldn't be to hard... just wire in a led light in parallel with one of the solenoids. The 5 wire connector is below the throttle body. 1 for power and 4 grounds (1 for each solenoid). So when the PCM grounds one of the solenoids it also grounds the led light. Though I have no idea where I would mount the light to keep it from looking retarted.

 

ahhhhhhhhhh this helps a lot now.
which package and how much id it cost ya? mail order is fine, but for me, it works, just not good enough. with what i have planned i need to do some more fine tuning and then some

 

Yeah the Chevy's say right in the cluster which mode its operating in.

Just log g/cyl and "ETC TPS" not just plain old TPS, its in accurate. Its about 10% off.

If you are logging the wrong one you'll notice you get 89% throttle with your foot to the floor. When logging ETC TPS it will read 100%

The actual DFCO system is not enabled on any US bound vehicle. Just play with it, raise the settings.... if you kept a copy of the stock flash yet, you have nothing to worry about it to change it back. Just try it, im not BS'ing here LOL

 

I got the MPVI Pro with the enhanced IO. Costs $650, but you have the ability to hook up a wideband or other external inputs for logging. The standard one costs only $500.

Like you said I prefer having this so I can fine tune everything. Hell I still haven't got my transmission settings perfect yet and ive been messing with them for a couple months. Mail order tunes are not a good idea unless you are bone stock. IMO

 

Ill have to try it out. Maybe GM just redid the code and HP Tuners doesn't know it so they stuck it under the DFCO tab. I haven't really gotten to deep into the logging yet... Thanks for the tips.

 

That's completely untrue. DFCO is enabled on LS1's and every other late model GM engine I've ever worked on. Why wouldn't be?

 

Do a search on it on www.HPtuners.com You find its is ILLEGAL to be used in conjuction with the lean cruise from the factory. It increases NOx emissions, wich is the by product of a lean condition. The engine will create heafty amounts of these emissions on decel to if its very lean, notice on a wide band the AFR stays at or about 14.7 on decel, even on a manual car when down shifting, with DFCO working on my 01' SS it gets to 16.1 AFR on decel with doing nothing but turning it on. It helped fuel mileage by 1-2 mpg, thats about it.

Not here to create drama on the topic, just going off my experiences with this is all. Never claimed to be a GM PCM engineer either.

 

I don't need to do a search, I'll just explain it to you.

DFCO is Decel Fuel Cut Off, with the key word being OFF. Under the right conditions on decels the injector on-time goes to zero with the torque converter left engaged. This doesn't create a lean mixture, it creates NO mixture; just air pumping through the engine, so no NOx increase. DFCO is in use on every late model GM engine I've been around.

Lean Cruise Mode on the other hand is not used on GM domestic applications. This changes the AFR using tables that ignore the O2 sensors so you are leaning the engine without good feedback and depending on engine condition, etc., can greatly increase NOx emissions.



Nor am I. I was just reading through the thread and kept noticing "DFCO ILLEGAL in USA" statements showing up in the posts and I like to keep the facts straight (and I was a GM PCM engineer).


That's todays lesson, now back on topic.

 

Can anyone report on fuel mileage improvements, hp/tq, and E.T.?

Thanks.