Ronny

iTrader: (1)

I believe your question was answered in a thread I started on hyway mode. Note spell hyway. I will see if I can find it. I believe it has to leave CL due to fact it is not stoich at 16/1. If CL BLM would rise to 160 or so.

Here it is: https://www.thirdgen.org/forums/diy-...hway-mode.html

hellz_wings

iTrader: (2)

I think it's supposed to run lean on highway mode, and then it falls out after a certain amount of time (around a minute I believe, but that can be adjusted), this is probably to prevent overheating and is probably normal.

The fact that it goes to 0 is odd though.. How new is your O2 sensor?

Solders18

thanks! another question is how can i tell if i am having lean misfires?

Solders18

its on the list for replacing. i haven't replaced it since i have had the car (3 years) and who knows if the prev. owner ever did. i am planing on doing it spring break or sooner. any suggestions on a preference? whats involved on installing a wideband?

Saar

dropping to near 0mV is totally normal when going into lean cruise.

Solders18

thanks for the confirmation

smoke29

Hope someone can shed some info on this question. I'm a newbie to programming, so I don't understand all the abbreviations, what the settings are for, etc. etc. But I have been playing around, and like people have said, it's the only way to learn how to do it. So, I basically have a '87 TPI set up, but not in a F-body. It's actually in a '41 Chevy coupe. 383 SB with al. heads, hi-flow Edelbrock manifold, hi-flow runners, 52mm TB, and a fairly mild cam. I'm going on a trip next week on old Rt.66 to Ca. from NY, and I want to enable Hyway mode for a little better mileage. I've read all the threads I could find on the subject, and I think I can get the chip burned properly. One thing is unclear to me. I don't have a electronic speedo, so the ECM doesn't read MPH-does it? So if it doesn't, do MPH settings for enableing hyway mode, or for that matter, any setting for any function in the bin, actually work when you set them? I just have the original speedo cable set up. Any info on this would be a big help in making me understand more on chip tuning. Thanks.

RBob

iTrader: (1)

The '87 TPI code doesn't have highway lean cruise mode. Will need to move to the '89 $6E code for it. Best to have a VSS input to the ECM. It is the simple 2K PPM digital/optical type sensor.

RBob.

smoke29

Thanks RBob. I should have said, I am using the $6e code. Probably won't have time to get and hook up a vss before I leave. Will it still work?

RBob

iTrader: (1)

Not with the stock code. The MPH test is a branch if less then or same for no highway mode.

RBob.

smoke29

RBob,
I don't understand what you mean (Not with the stock code. The MPH test is a branch if less then or same for no highway mode). As I said I'm a newbie to programing.
Can I enable it by setting the RPM, Lv8, and set the MPH to 0? Or some other way to fool the ECM?

RBob

iTrader: (1)

It is as I posted, not with the stock code unless there is a VSS input to the ECM.

If you want to patch the code then it can be done. And by patch I don't mean a change in a calibration parameter.

RBob.

Saar

not the most elegant solution, but could set the MPH calibrations to 0, then change the BLS to BLO. total of 3 bytes changed. but the problem of potentially unwanted highway mode activation would be an issue...

smoke29

OK. Thanks for the info. I was able to find a vss and ordered it overnight from Ca. so I should be able to get it hooked up and working before we leave next week. Will post how it works out.
Thanks again for the help.

smoke29

Well, I got the VSS installed and worked on getting hyway mode turned on with a friends help. We couldn't get it to work, and maybe someone can tell me if this is why. When I put the car together originally, no vss. So to get the converter to lock up in 4th. gear, a single 12v. wire was run to the trans to lock the TCC. The question is, is there a signal requirement for 4th. gear lockup to the ECM for it to go into hyway mode? Right now, the way it's wired, there is no provision to signal the ecm when it's in 4th gear. Any ideas?
Thanks.

morgsie

iTrader: (1)

There is a bit (I believe it is HighGr) to determine if the switch in your valve body is NO or NC. I do not know if you need to be in 4th for HiWy mode.

lakeffect2

HIghway Mode (HM) Mdoes not seem to be engaging for me. in EBL P4.
Are there option words that must be checked (or unchecked) as part of the conditions for HM to be met?

Are there items which when set can be too far out of range for HM to be active.?

RBob

iTrader: (1)

No option flags for HM, unless you want it to be able to run from open loop mode.

Check the qualifiers, having the MPH enable threshold at 150+ MPH will do it. There is also the CTS & MAP thresholds, along with the in & out times.

RBob.

lakeffect2

Thanks, I'll will double check all the entries again. Might have map too high?

RBob

iTrader: (1)

The MAP threshold setting would have to be too low. Once the actual MAP is above the threshold (higher load), the ECM exits HM.

RBob.

usc iroc

Just want to verify something....when in Hiway mode should my ECU switch to OL?

7747 TBI $42

RBob

iTrader: (1)

Yes, but the closed loop flag may remain set. See if the INT gets locked to 128 and the O2 flatlines in the double digits. Note that the stock '7747 doesn't have lean cruise highway mode.

RBob.

usc iroc

OK..I will look back at my datalog and see if it that occurs. I am running the ASDU3 bin that I believe you and a few others worked on along with the definitions file with the Hiway/ESC patch. If that matters?

Thanks for getting back to me

usc iroc

I attached my bin and the latest datalog and I do not see that the INT or 02 do anything out of the ordinary. I am leaning toward it not initiating. Let me know your thoughts.

srgould41

Lots of good reading here. I was working out the settings for my engine then read the warnings about EGR. I don't have one. I do run a barn door kinda truck so any MPG help is appreciated. If I would only get 10% improvement, as EagleMark found on his "brick", then it might not be worth the effort. I don't normally see more than about 200 highway miles a month. I get about 11 MPG now. 10% would be just over 12. That's about 2 gallons difference per trip vs. the chance of burning out my engine.

EagleMark

Although the EGR does cool off pistons it's been proven by Ronny and others now in different conversations it's not rquired for the Hyway Lean Cruise to be safe.

Saar

lean out the AFR enough and you'll get combustion temps noticably below that of stoich operation.

srgould41

I ended up enabling HLC today. I didn't think it was working because I didn't see the BLM freeze at 128. It was actually around 124. INT did freeze at 128. Weird. I knew it was working because the log file showed going into and out of Open Loop.

My last highway run showed an average of 15.1 MPG in the hack. This run showed 18.6 in the hack. Temps were good and no knocks.

Steve

usc iroc

I have yet to get mine to work..... I have attached my latest log and bin. I would appreciate any help guys

srgould41

Everything I saw says your computer should have gone into hiway mode.

RBob

iTrader: (1)

The BLM gets locked at it's current value. This is done as it adjusts the commanded for the actual AFR to be more accurate.

RBob.

srgould41

RBob, I have read that BLM will freeze. My logs showed INT freezing and BLM kept moving. It's opposite of what I expected to see in the log file. It does work, though and I am happy.

usc iroc

My BLM did freeze at 126 so I guess it is entering into hiway mode. I just didn't really do any major adjustments so I guess that is why I didn't notice any changes in the MPG gauge.

Ronny

iTrader: (1)

PW should change. My A/F clearly changes.