Path: utzoo!utgpu!attcan!uunet!husc6!cmcl2!rutgers!iuvax!silver!commgrp
From: commgrp@silver.bacs.indiana.edu
Newsgroups: sci.electronics
Subject: ??: computer-controlled engines
Message-ID: <7200006@silver>
Date: 3 Aug 88 18:20:00 GMT
Organization: Indiana University CSCI, Bloomington
Lines: 48
Nf-ID: #N:silver:7200006:000:2085
Nf-From: silver.bacs.indiana.edu!commgrp    Aug  3 13:20:00 1988




also posted on rec.autos.tech:

What experiences have people had with car engines controlled by 
digital computers?  Are they a mature technology, or are they like 
color television in the 1950's?  Most car problems are electrical in 
nature; electronic engine control would seem to decrease reliability.  
[On the other hand, car seatbelt buzzers are the most reliable devices 
in the universe!  How did they do that?? Must be a spinoff of SDI! :-]

A friend owned a Datsun with computer-controlled engine, circa 1983. 
Her car randomly failed to start.  Replacing the $300 computer module 
solved the problem for 2 weeks.  After several new computers, another 
friend discovered that the connector was corroded.

I've heard the following rumors about digital engine-control 
computers:

1. They contain a register which records the highest speed at which 
the car has been driven. This can be read by dealers, who will refuse 
to repair engines under warranty if the number is too high.

2.  A new car's computer assumes default parameters, and sets new ones 
as it "learns" the car's performance over 50 miles of driving.  If the 
car battery is disconnected, the computer forgets the learned values, 
and the engine runs less well for 50 miles while the computer retunes 
itself.  (Is the highest-speed memory erased by disconnecting the 
battery?)

3.  The federal government has funded research (thusfar unsuccessful) 
to discover a ray like Batman's which stops car engines, for law-
enforcement purposes.  Big Brother plans to require a remote-disable 
feature on engine computers.

4.  Radio-frequency interference can jam the computer, causing various 
effects like engine stop or full throttle.  This definitely happens 
with radio transmitters mounted in the car; there was a long 
discussion of it on rec.ham-radio last year.  Manufacturer's 
recommendation: Don't install any 2-way radios. What happens when you 
are next to a semi with a 100-watt CB "linear" amplifier??

--

Frank        W9MKV
reid@gold.bacs.indiana.edu
Cogito, ergo Spam: I think, therefore I ham.