jeepguy553

The first datalog off the Jeep is done. The results have already been touched on in another thread. Here's the rundown.
Run engine for about 4 minutes. CTS comes up fine. Idle will not go below 1000rpm for some reason. (I am running off the OEM chip right now.) I am getting a constant 5 in the knock counter and a code 42 (ESC Fail) straight down the line. SES light stays ON with engine running. I also noticed that my alternator may have nose dived...battery volts are sitting at about 11.9 all the way down. IAC steps look like they are a little erratic until the engine starts to warm up to operating temp. Is this normal? My dizzy timing is set at about 6 BTDC unless someone has fooled with it. Could the dizzy timing be hosed up?

RBob

iTrader: (1)

A code 42 is an EST failure (not an ESC DTC which is code 43). Check that the BYPASS/EST connector has been re-connected from after timing the engine. If it is then there is a problem with either the ignition module, ECM, or EST related wiring.

RBob.

jeepguy553

By ignition module, do you mean the 8-pin module or the one mounted with the fuel pump relay?

jeepguy553

Don't I feel like an idiot...the set timing connector was disconnected. I plugged it back up, pulled the neg cable and let the ECM clear codes, and fired it off. Guess what...no error codes.
I did another datalog at idle with a custom BIN. The idle is even higher at about 1350 RPM. I have GOT to get that idle thing fixed. What am I doing wrong? I am headed out to do the IAC reset again. I'll log and post results after I do it.

RBob

iTrader: (1)

You guys and your idles. . .

https://www.thirdgen.org/techbb2/sho...hreadid=225984

IIRC the '8746 & '7747 idle control qualifiers are the same.

RBob.

P.S. I think we need a DIY-PROM rule that if you don't list your ECM someplace in your first post we delete the thread, or something. . .

jeepguy553

Sorry...8746, $61. Please don't delete my first real tuning thread!!
Okay, I did the IAC reset and managed to knock the idle down to about 975rpm in PARK. The screw is ALL THE WAY out and the blades are completely closed. I just looked over the thread Rbob posted. Now I have a little better understanding of the IAC settings. Thanks Rbob!
I knocked the IAC steps down to 109 and it seemed to help a little bit. Could I go into the IAC vs CT or the Idle vs CT and move things around a little to see if I can knock it down to about 750rpm in PARK? I do have the P/N switch wired up and it shows up in the Flag data tab on WinALDL. TPS is about 2%. Maybe less. I need to go look again.
New thread coming up about A/D counts and temps for EGR solenoid controls.

Ronny

iTrader: (1)

i would not be concerned about dropping the IAC values. my new 454 TB is going on and my current IAC values are 1/2 of what they should be. if i have low idle that is OK by me. manual trans so no big deal.. i would rather work up idle speed than down. besides with new cam should sound very cool. especially with hooker aerochambers and true duals.

jeepguy553

That's exactly what I want...a lower idle.

RBob

iTrader: (1)

This gets a little tricky as the qualifications as to which idle speed parameter is used depends upon several variables. In a nutshell the idle speeds at LD536 & LD535 are used when not in a closed loop idle. This includes a cold engine along with being in park/neutral.

In park/neutral and coolant less then the value at LD545 the idle speed at LD535 is used.

In park/neutral and coolant greater then the value at LD545 the idle speed at LD536 is used.

In drive and not in closed loop idle the idle speed at LD536 is used.

Once in closed loop idle control the idle speed at LD52C is used, pending low battery correction, A/C, etc. . .

Hope I got that correct!

RBob.

jeepguy553

So, basically I need to get into the hex editor and change the values in thos locations to get the idle I want at different engine operating conditions. I think I can do that. I'll let you know how it goes. The low battery thing you are talking about is what I am seeing right now. I think my 100-amp alternator just became a 0-amp alternator. Good thing I have a spare 60-amp for emergencies like these.

jeepguy553

Here's the changes I made to the idle qualifiers
1.) LD535 changed from 1400 rpm to 900 rpm ($48h)
2.) LD536 changed from 900 rpm to 750 rpm ($3Ch)
3.) LD52C changed to 750 rpm ($3Ch)
4.) LD52A changed to 650 rpm ($34h)
5.) Moved entire IAC vs Coolant Temp down 20%
6.) Changed Batt Volts Stall Saver Threshold (LD530) to 11.0V

I am considering moving the TPS% for Idle Adjust (LD514) to ~2.5% from 1.96%. Is this a bad idea?
Ih yeah. I did all this stuff, started the Jeep, and it ran out of gas.

brennanw

A quote here from the famous RBob:

"If you have a manual leave the park/neutral switch line open. The ECM needs to see that the vehicle is in drive in order to control the idle speed via the Idle Spd vs Coolant table. Else it just uses the max RPM allowed parameter for 'when in park/neutral'. Try it with B10 open and see how things go."

Found in this thread https://www.thirdgen.org/techbb2/sho...hreadid=225984

jeepguy553

B10 was open. I just wired the P/N switch up today. I used the switch on the Hurst shifter instead of the one on the TF727 auto tranny...because that one is crap. I'll be using the reverse light switch on the shifter too when I get around to wiring it up.
I am not quite sure what you are saying. Are you saying that the P/N switch (closed in P or N) tells the computer to up the idle in P or N or is it the other way around?

jeepguy553

Just read another thread. Let me get this straight here. When I put the 10K across the A and B pins, it forces the ECM to target a 1000rpm idle? That would definitely explain why I can't get rid of the high idle. Is there somewhere in the ECM (maybe a constant) that allows us to change the ALDL idle?
Can I run the engine in open across A-B and still get a datalog?

Bill usn-1

To log with winaldl you should not use any jumper.
The orange serial data wire and a blk/wht gnd wire are all you need.
If you want to do an IAC reset than just hook the wht/blk wire to gnd also until you disconnect the IAC. then disconnect the wht/blk wire and turn the key off.
Restart and set throttle plate.

jeepguy553

Isn't there a value that needs to be changed to AA for some reason when using a burned chip?

dimented24x7

iTrader: (2)

Thats the mask id byte. No need to do that unless you arnt calculating the checksum for some reason. When the computer sees that, it continues after a checksum err. rather then halting.

jeepguy553

Cool...so just leave that set at $61. Is there an idle value for ALDL mode that can be changed? It doesn't show up in my ECU file.

RBob

iTrader: (1)

RBob.

jeepguy553

So how would I change that to say...750 rpm?

Z69

Hex Editor
TunerPro
TC
among others.

Edit your ecu to show that address.
Then you can change the value.

I'd expect more of an Ex. NN

Why would you want your ALDL mode to IDLE at 750? Isn't that there to verify it is in ALDL mode? WAG

jeepguy553

I guess I could leave it like that. I was more or less just wanting to see that the changes I am making are actually working. The changing of the value isn't the question...it's what to change it to. The decimal value for $80h is 128...not 1000. that's what I was asking.

Z69

Ah, good reason, and has no real effect on anything important.

Get the Hac for your code.
They usually tell how the value is converted to a <= 255 number.
For 8D it's divide rpm by 25 I think.
6375/25=255. RPM code limit in 8d.
Haven't been in the ANHT hac for a while.

Open the ecu editor tool in TP for a RPM value. It will show the math I think.

This is great, learning all the 746 stuff w/o all the work.
I may use a 746 for spark control till I get the EFI parts for my Camaro.

jeepguy553

thanks, Z69. I just found it in the code of the 8746 hac. It says:

If you look farther down in the code, there are these two lines:
Do the math and you will find that 1000/12.5=80 and 550/12.5=44.
Got it. Thanks!!!

jeepguy553

I just realized something else. If I have been logging with the 10K setting (across A-B) on the AutoPROM, can I still log in the open across A-B position? That would really change things a lot...including my ability to see what my engine is really doing in response to the changes I am making to the BIN.

Z69

I saw the 12.5 in another post.
It was for SA with a 3200rpm limit. So I didn't pass it on.
Apparently some of the tables use a
divide by 12.5 factor. When I know the motor goes higher than that.
And it need to know the number since it calc how much adv vs rpm using slope.
Means another calc is in there for rpm.

Something else to find.



Could you e-mail me that 746 Hac?

jeepguy553

How's this as a link to it...
8746 hac on Moates.net

Z69

I read ref to an ALDL mode in the code.
Not all have it. Search the hac for ALDL and see what all it does when in that mode. Some do some strange things.
For diagnostics I guess.

jeepguy553

That hac has it. It is the one I have at home. I seem to remember seeing the ALDL stuff in that hac down pretty far in the code part.
EDIT: There it is. The ALDL List starts at LD414. It's pretty far down in the hac.

Z69

Thanks, I downloaded that file a while ago. The DSM extension threw me when I looked at it the other night. Was looking for all my bin & ecu files. So didn't open.
Or move to the laptop.

All of the codes have ALDL. You will have a section that has what data is transmitted when and what order.
Not all have a mode though. I think.
I'm not sure what 8d does when the pins are shorted. I don't recall much happening. I recall Craig saying to log w/o the pins shorted though. But that was a 165 post IIRC.

I spent about 8 hrs just on the anht hac.
Every morning at breakfast.
Just to get an idea of what's in there.
It's 313 pgs. Then I got a better commented hac...

jeepguy553

The ANLU hac is pretty big too. I just scanned through it using the "FIND" function in IE5.5. I found several ALDL routines, but none really told me if it will transmit data without the 10Kohms across A-B. If it will, I am there. I'll be able to see what my BIN changes are doing to the engine.
Oops...I just realized something I did concerning the EGR stuff. I hope it isn't too late to fix it...

jeepguy553

I just found the ALDL Idle in the $61 code. I used the TunerPro hex editor. It is there alright. At location 0x00052B there is a value of $50h....80dec...calculates to 1000rpm ALDL Idle speed. Two things to do now.
1.) Edit the ECU I am using to show this value
2.) Change this value to something a little more livable like 750 rpm.