http://alfa-wahnsinn.de/L-jetronic-america_gtv6.pdf
I found whilst looking for where to purchase a new intake bellows , as one of mine is cracked big time - I might give this articles repair remedy a go - ie using Shoe goo!
Which I also paste here - very long - 12 sections - which I divided into separate "pages"includes
Intro
Step 1 Eliminate Air Leaks http://firstfives.org/phpBB-3.2.1/phpBB ... 744#p32744
Step 2 Electrical Grounds http://firstfives.org/phpBB-3.2.1/phpBB ... 745#p32745
Step 3 Comply with Alfa Tech Bulletins 87,01 and 89,02 http://firstfives.org/phpBB-3.2.1/phpBB ... 746#p32746
Step 4 The Cold start and warm up system http://firstfives.org/phpBB-3.2.1/phpBB ... 747#p32747
Step 5 Fuel pump and Fuel Pressure regulator http://firstfives.org/phpBB-3.2.1/phpBB ... 748#p32748
Step 6 Throttle Position Switch http://firstfives.org/phpBB-3.2.1/phpBB ... 749#p32749
Step 7 Injectors http://firstfives.org/phpBB-3.2.1/phpBB ... 750#p32750
Step 8 Air Flow Meter http://firstfives.org/phpBB-3.2.1/phpBB ... 751#p32751
Step 9 Ignition Timing http://firstfives.org/phpBB-3.2.1/phpBB ... 752#p32752
Step 10 Altitude compensation Device http://firstfives.org/phpBB-3.2.1/phpBB ... 753#p32753
Step 11 Idle Adjustment http://firstfives.org/phpBB-3.2.1/phpBB ... 754#p32754
Step 12 Advanced Air Flow adjustments for best emmisions and power http://firstfives.org/phpBB-3.2.1/phpBB ... 755#p32755
Last Step, Supercharging + Trubocharging http://firstfives.org/phpBB-3.2.1/phpBB ... 756#p32756
and a big thanks to Greg of Hiperformance who published this information
I also found a L jet manual published by Bosche
http://www.cardiagnostics.be/-now/Educ ... Manual.pdf
http://alfa-wahnsinn.de/L-jetronic-america_gtv6.pdf
How to Understand, service and modify Bosch Fuel Injection & Management by Charles O. Probst. Robert Bentley Publishers. ISBN 0-8376-0300-5
http://www.hiperformancestore.com/Ljetronic.htm
GREG'S BOSCH L-JETRONIC FUEL INJECTION IDLE ADJUSTMENT, DIAGNOSTIC AND TUNE UP PAGE, Latest revision Sept. 4th 2003 includes changes to the introduction, Step one, testing procedures for the Altitude Compensating Device on Step 10 and the creation of Step 12 which involves advanced Air Flow Meter instructions for adjustments for Max power and best emissions.
The Bosch L-Jetronic system is used on all U.S. Spec Alfa Romeo GTV6s, Milanos, and 1982-1989 Spiders, BMW E12 5 series and various 3 series cars, The Datsun 280Z and 280ZX, All U.S. spec fuel injected Fiats and Lancias, The 1984-1989 Nissan 300ZX, The Toyota Supra Mark 1 and many others.
I am writing this article specifically from the point of view of a U.S. Alfa Romeo GTV6 and Milano, however if you own any car with Bosch L-Jetronic injection the article will still help you. However the components of other cars using L-Jetronic will be located in different locations, but the testing procedures are the same.
The components from the various types of cars DO NOT interchange. This is especially true between the Japanese and European cars.
Introduction, please read this before starting any work on your injection system:
At one time so many People asked questions about idle problems that I decided to write complete idle adjustment instructions. However, with the L-Jetronic system our cars use, about 90% of the complexity deals with about 5% of the running. In other words most of the system's components deal with things like cold starting, warm up, idle, full throttle etc. That means that by the time you have checked and adjusted everything that affects idle you have really checked and adjusted most of the injection system. Just add new plugs, a cap and rotor and you have done a complete tune up. So this article has really turned turned into a complete fuel injection and tune up article.
I am writing this article specifically for the U.S. Alfa Romeo GTV6 and Milano, however if you own any car with Bosch L-Jetronic injection the article will still help you. However the components on an injected Fiat X1/9, Fiat Spider, Lancia or other L-Jetronic car will not be located in the same place they are on a GTV6.
You can use this article in a few ways, first you could follow it through step by step. This would very thoroughly check out your injection system. I recommend this method if you have plenty of time, or if your car has more than one problem or if you just purchased the car and want to get it running just right. If your car has one simple problem you can use this article as a sort of trouble shooting and testing guide for specific components. To make trouble shooting easier I have included the symptoms associated with a defect for each part of the injection system. The sections showing
these symptoms can be found quickly by looking for the *Symbol. If you follow all of these instructions perfectly you will almost certainly gain some horsepower! Even on a perfect car with stock settings you will gain a tiny amount, and on most GTV6s which are not in the best state of tune you could quite probably pick up ten or more horsepower! If your car is in fine tune but you are looking for ways to gain a little power look for the @ symbol.
This article is written with economic realities in mind. I am not going to tell you to go out and buy Bosch testing equipment or to buy expensive new parts you may not need. We will be testing everything with an inexpensive ohm meter and a test light I will also be telling you how to repair most of the parts so you won't need to buy a new $100 hose or sensor. Everything I say or recommend has been done on my own vehicles with great success.
Some people may ask, "Greg, what qualifies you to write this?" Well I should say I have no formal automotive training but you can bet I know more about V6 Alfas then the mechanic at your local Pep Boys. I have been riding in or driving Italian cars my whole life. The first car I ever rode in was a Fiat 600. My father has been working on Italian cars for over 40 years, at one time professionally. I started helping him in the shop and paying attention from a very early age. I have owned many Italian cars and I currently own 4 including one I commute to work in. I am not someone who owns a show Alfa that never leaves the garage and drives a Honda to work. I do all my own work and my cars are very reliable. So if you want to trust me read on, if you don't that's OK too. Of course you should also have and read the official Bosch and Alfa Romeo publications relating to anything you are doing on your car. If anything the official publications contradicts anything I have written then go with the official advice.
9-04-2003 I now consider this article to be complete. I may edit it from time to time, but for the most part it's done. This L-Jetronic article has proven highly successful. At one time on the forum at gtv6.org (where this article started) it seemed there was a question almost every day about a fuel injection problem. Today questions posted there about L-Jetronic are quite rare. That's great because it means more people are successfully fixing their Alfas, Fiats, and Lancias themselves which helps keep ownership costs down which in turn helps the cars survive.
Thanks for visiting,
Greg Gordon