Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   Porsche 928 Technical Forum (http://forums.pelicanparts.com/porsche-928-technical-forum/)
-   -   How to Reset L-Jet with new O2 Sensor? (http://forums.pelicanparts.com/porsche-928-technical-forum/587538-how-reset-l-jet-new-o2-sensor.html)

MPDano 01-24-2011 04:34 AM

How to Reset L-Jet with new O2 Sensor?
 
Does anyone know the procedure? I just installed a new O2 Sensor and wanted to make sure the Computer know's the change.

DPW928 01-24-2011 05:13 AM

The computer is analog (no programming) and the signal is just a voltage input so there shouldn't be any initialization required. i.e. plug and play.

MPDano 01-24-2011 05:56 AM

Oh, so the procedure I saw was for an LH and not L?

Is there a way to manually adjust the A/F on the L-Jet System?

harborman 01-24-2011 06:26 AM

I never saw an "analog" computer. Everyone I saw are digital. Maybe it has fixed firmware and D to A and A to D converters, but the processor must be digital unless this is something real unusual. To my knowledge computers use binary 0's and 1's. Instructions, data and addresses all stored as binary.

Quote:

Originally Posted by DPW928 (Post 5804366)
The computer is analog (no programming) and the signal is just a voltage input so there shouldn't be any initialization required. i.e. plug and play.


stepson 01-24-2011 06:39 AM

Quote:

Originally Posted by MPDano (Post 5804426)
Oh, so the procedure I saw was for an LH and not L?

Is there a way to manually adjust the A/F on the L-Jet System?

If it makes you feel better :), you can disconnect the battery for about 30 minutes and then reconnect it. The L-jet should now be reset.

To change the A/F mixture: that is done by removing a plug that covers a screw on the barn-door flappy. It's in the WSM, but I'm at work and do not have access to which section and page it's on.

DPW928 01-24-2011 06:57 AM

Quote:

Originally Posted by harborman (Post 5804477)
I never saw an "analog" computer. Everyone I saw are digital. Maybe it has fixed firmware and D to A and A to D converters, but the processor must be digital unless this is something real unusual. To my knowledge computers use binary 0's and 1's. Instructions, data and addresses all stored as binary.

Analog computer - Wikipedia, the free encyclopedia

harborman 01-24-2011 08:48 AM

Not as used in operating most complicated arithmetic decisions as your PC is. Yes you can call a slide rule an analog computer but it isn't going to operate your fuel system in real time unless you have a fast hand and quick foot and able to read gauges at nano second speeds to control O2 and fuel ratios! Not a computer as people consider them today! PS. I have one (slide rule) if you need it, sell cheap! Hand operated computer I guess!

Quote:

Originally Posted by DPW928 (Post 5804546)


DPW928 01-24-2011 09:43 AM

Quote:

Originally Posted by harborman (Post 5804744)
Not as used in operating most complicated arithmetic decisions as your PC is. Yes you can call a slide rule an analog computer but it isn't going to operate your fuel system in real time unless you have a fast hand and quick foot and able to read gauges at nano second speeds to control O2 and fuel ratios! Not a computer as people consider them today! PS. I have one (slide rule) if you need it, sell cheap! Hand operated computer I guess!

Think we're telling our age when talking about slide rules.:D I believe the first O2 processors (is that better?) were transistor based and just converted the input voltage to an output on/off voltage frequency. The idle position and WOT switches just turned the processor on and off.

Landseer 01-24-2011 09:43 AM

Here


http://forums.pelicanparts.com/uploa...1295894627.jpg

harborman 01-24-2011 10:02 AM

I happened to find my old slide rule, case and book in a box hidden for some years. The darn thing still looks good. Don't think I can get on the internet with it!

Quote:

Originally Posted by DPW928 (Post 5804849)
Think we're telling our age when talking about slide rules.:D I believe the first O2 processors (is that better?) were transistor based and just converted the input voltage to an output on/off voltage frequency. The idle position and WOT switches just turned the processor on and off.


Landseer 01-24-2011 10:06 AM

No, but if your's is like mine its a foot long with a leather carrying case and a belt loop, so you can wear it like a sword.
Used it till the HP45 came out. And the HP 67.

Landseer 01-24-2011 10:09 AM

No wonder we are drawn to 928's.

JhwShark 01-24-2011 10:12 AM

Quote:

Originally Posted by Landseer (Post 5804888)
No, but if your's is like mine its a foot long with a leather carrying case and a belt loop, so you can wear it like a sword.
Used it till the HP45 came out. And the HP 67.

I got the drag strip type as well, but also a circular one...if I feel like NASCAR I can just keep turning left...NOT

MPDano 01-24-2011 10:18 AM

Quote:

Originally Posted by Landseer (Post 5804850)

I tried to push in the reset button with my finger, but it still kept clicking. I will try a screwdriver next time, it probably needs to be pushed in further.

DPW928 01-24-2011 10:29 AM

Quote:

Originally Posted by harborman (Post 5804878)
I happened to find my old slide rule, case and book in a box hidden for some years. The darn thing still looks good. Don't think I can get on the internet with it!

No internet but it is virus and malware proof. :)

harborman 01-24-2011 01:38 PM

These young kids just have no idea of punched paper tape and IBM cards! But it was fun at the time. My first program written on DEC PDP-11, predissor of the PC, cost over $48k in 1974.

Quote:

No wonder we are drawn to 928's.

neil30076 01-24-2011 02:32 PM

Quote:

Originally Posted by harborman (Post 5805296)
These young kids just have no idea of punched paper tape and IBM cards! But it was fun at the time. My first program written on DEC PDP-11, predissor of the PC, cost over $48k in 1974.

I'm with you - 96 column cards, ICL mainframes ( in UK), later VAX!
You might be amused by this picture, argueably the worlds first laptop ( circa 1987_) still works !

http://forums.pelicanparts.com/uploa...1295911897.jpg

DPW928 01-24-2011 06:13 PM

Quote:

Originally Posted by harborman (Post 5805296)
These young kids just have no idea of punched paper tape and IBM cards! But it was fun at the time. My first program written on DEC PDP-11, predissor of the PC, cost over $48k in 1974.

I still have tinnitus due to too many hours/days/months in front of an IBM 026 card punch machine. Used the IBM 1301 punched card accounting machine until we (USAF) upgraded to a Burroughs 3500. Talk about sitting in tall cotton. It had data and programs on tape reels. Still had to input with punched cards though.:mad:

Actually, I do prefer the new systems. even though I can still decipher the hollerith coding on punched cards. :)

tmpusfugit 01-25-2011 05:10 AM

my first laptop was a Toshiba 1100 with 2 3.5" floppy drives, and that was early 1987...by 1989 I was working on the design team for Compaq Computer Corp developing the first cigarbox laptop, a turkey called the LTE.....and my first real computer was in 1965, an analog called a MK1-A gun fire control computer, developed and used in WWII. A massive electromechanical monster that computed with some degree of accuracy 38 variables. It worked pretty well as we could drop 5" shells into a 50 yard radius at 5-7 miles range while the ship was in motion....we could shoot 15 miles but not so accurate....my first mainframe experience was 1984 on an IBM 4381......and an HP 3000 too....and they didn't talk to each other....what fun that was....my first electronic computer was in 1978, a Xerox 820 with twin 8" drives and 64k of computing power!

harborman 01-27-2011 06:05 PM

My DEC PDP-1170 at work, circa, 1974. 16K of core, paper tape input, 1.2 Meg hard drive. TTY terminal. Cost over $50K in 1974 dollars! Me at console!http://forums.pelicanparts.com/uploa...1296183841.jpg


All times are GMT -8. The time now is 02:05 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.