BLM's & Learning to tune My '84

Lockman

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Dec 6, 2018
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I need some advice , please. Completely stock , From chip thru ECM, to fuel pump .Can not get the idle below 1000, following the basic IAC & TPS procedure? Set the New TPS at .43 , tighten down, go to read laptop scan tool, & it reads 5.7? Blms last week were 139 , this time 150 ? New MAF reads 6.0 to 7.0 ? Can Not locate any vacume leaks using throttle body spray trick ? Do not know fuel pressure, but has the stock Bosch 233 ?.

It is an 18 year old complete stock rebuild , in my CJ5 . 17400 miles since ? any suggestions would be appreciated
1975-Jeep-CJ-5-Classic'82 Buick V6 Turbo SFI.jpg
. :cautious:
 
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Lockman

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Dec 6, 2018
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Hi Ya'all... I found this from 2002 .. ( and I'm quoting) "
I use Turbo Link and sometimes the ECM somehow goes into ALDL mode instead of NORMAL. When this happens I notice the idle speed increases up to 1000+ RPMs. According to the T-Link manual it states, "The Assembly Line Diagnostic Link (ALDL) mode allows you to read different data from the ECM. This mode is sometimes referred to as the "Special State" or the "10K Ohm State" in some repair manuals. Fuel injected GM vehicles automatically raise the idle speed to 1000 RPM and add extra spark advance to the spark calculations when in the mode. The ALDL mode feature is primarily used to check the operation of the Electronic Spark Control (ESC)."

Just thought this might be your case as I have experienced this on my car.


I've got hope here....'cause this is exactly how mine is acting! My Question is : I'm using a Bluetooth Adapter on my laptop as my Scan Tool . When i'm plugged into the ALDL, Does that take me out of NORMAL mode ???

I realize that alot of you guys are into racing and I used to be when I was younger. Now , I just want to tune my engine , the right way. I'm thinking that when I use my volt meter to set TPS & IAC , that's where I can only Idle down to ~ 1000 rpm's ? ( No proper TPS reading adjustment , then ? )
Somehow , could it be 'Stuck" in the ALDL Mode ??? How Do I get it out ? I think that my stock chips ( verified ) & ECM are functioning well. Please, any advice is needed and really appreciated.
------ Lockman
 

hotairgnx548

hotairgnx548
Apr 7, 2010
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bowling green ky
I need some advice , please. Completely stock , From chip thru ECM, to fuel pump .Can not get the idle below 1000, following the basic IAC & TPS procedure? Set the New TPS at .43 , tighten down, go to read laptop scan tool, & it reads 5.7? Blms last week were 139 , this time 150 ? New MAF reads 6.0 to 7.0 ? Can Not locate any vacume leaks using throttle body spray trick ? Do not know fuel pressure, but has the stock Bosch 233 ?.

It is an 18 year old complete stock rebuild , in my CJ5 . 17400 miles since ? any suggestions would be appreciatedView attachment 336822. :cautious:
 

Lockman

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Dec 6, 2018
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!st : It goes to the mass air sensor.
2nd :It's below the Master Cylinder , and it starts with the OEM vapor canister ( recently refreshed )
3rd :TPS is pictured ? : Mounts at the front facing side of the Throttle Body, To the right of the Waste Gate Actuator.
After attempting The IAC reset procedure again today, I Cannot get the Idle rpm below 950 ? For The life of me , I cannot locate any Vacuum or exhaust Leaks ??? Just recieved a Kirbins adjustable fue regulator & Gauge. Goes in tommorrow morning . Thanks for your help , Ideas & support . I'll keep going , but i'm baffeled & hornswoggled ?????-------Lockman
' 84 readings 3-15-2019.jpg
 

Lockman

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Dec 6, 2018
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I Installed a New IAC Stepper unit a month ago. I have seen it it fluctuate between 1 up to 100 Steps ? Thanks for your interest & Help I'll get a better Data Log picture up a little later today. ( Working on a self made oil leak right now.' 84 readings 3-15-2019.jpg' 84 readings 3-15-2019.jpg
!st : It goes to the mass air sensor.
2nd :It's below the Master Cylinder , and it starts with the OEM vapor canister ( recently refreshed )
3rd :TPS is pictured ? : Mounts at the front facing side of the Throttle Body, To the right of the Waste Gate Actuator.
After attempting The IAC reset procedure again today, I Cannot get the Idle rpm below 950 ? For The life of me , I cannot locate any Vacuum or exhaust Leaks ??? Just recieved a Kirbins adjustable fue regulator & Gauge. Goes in tommorrow morning . Thanks for your help , Ideas & support . I'll keep going , but i'm baffeled & hornswoggled ?????-------LockmanView attachment 336999
' 84 readings 3-15-2019.jpg
 

Lockman

Appreciate and Admire other' s Knowledge
Dec 6, 2018
61
8
8
43
!st : It goes to the mass air sensor.
2nd :It's below the Master Cylinder , and it starts with the OEM vapor canister ( recently refreshed )
3rd :TPS is pictured ? : Mounts at the front facing side of the Throttle Body, To the right of the Waste Gate Actuator.
After attempting The IAC reset procedure again today, I Cannot get the Idle rpm below 950 ? For The life of me , I cannot locate any Vacuum or exhaust Leaks ??? Just recieved a Kirbins adjustable fue regulator & Gauge. Goes in tommorrow morning . Thanks for your help , Ideas & support . I'll keep going , but i'm baffeled & hornswoggled ?????-------LockmanView attachment 336999
I Mistakenly wrote where the TB air duct goes. It Goes to the original Air Horn with a Fresh air filter. The Vapor canister is what I rebuilt & Refreshed.:oops:
 

Lockman

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Dec 6, 2018
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Yes Sir....I Installed a new Kirbins Fuel pressure regulator today. About 28 psi vacume off / 42 psi on vacume . Not up to temp in this shot either, but my heart started to flutter when I saw these BLM' ! I also repaired an oil leak ( My Fault ). Would these two things bring the BLM down to near perfect ? I'll do the IAC reset procedure tomorrow. Another Question : Should The engine be at operating temp when I do that ? And Last , I have never got this engine past 160 - 165 ? It has duel electric fans on a 2.5 inch radiator ?
 

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Ttype6

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Aug 17, 2004
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Your blm is 128 because the engine is so cold that it hasn't gone into closed loop operation yet. There is no perfect blm. It is just a number that shows how much fuel is being added or subtracted from the initial program based on information from the O2 sensor. You need a shot of what's going on at full operating temp.
 

Lockman

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Dec 6, 2018
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I know the ecm needs to see above a certain temperature before it will go into closed loop. I think its 150 degrees but i'm not sure. It also has to see the O2 sensor working. My 02 Is working at ~145 Degrees
 

Lockman

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Dec 6, 2018
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Your blm is 128 because the engine is so cold that it hasn't gone into closed loop operation yet. There is no perfect blm. It is just a number that shows how much fuel is being added or subtracted from the initial program based on information from the O2 sensor. You need a shot of what's going on at full operating temp.
Ttype6,
Thanks for opening my eyes to the Temp / closed loop issue. I had installed a mechanical Temp gauge and had the sending unit in a ' T ', which was the Wrong way to do it . I straightened that out today and i Logged this :
 

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Lockman

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Dec 6, 2018
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Yes Sir,
Everthing is stock on my '84 Hot air. I did install a new Heated Denso O2 & a Kirbins Fuel pressure regulator & Gauge. Today , I dialed down the fuel pressure too ~ 40 , Line off , about 25 - vacume line on. I logged another data file and took this Pic.
I also noticed when I disconnected my ALDL Bluetooth Adapter , that I heard the Rpm's go up a bit ?. What's up with that? . Is that cuz it goes into regular mode ? My factory ALDL connector only has 5 ) contacts on the top row. I appreciate anyone's & everybody's thoughts & advice on this.
 

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