No drop down idle tester?

[Gary Sullivan]

Anyone have any tips for how to set 75 fuel injection idle without the Idle Drop Tester or do I need to find one somewhere? (page 6-38 of the 75 service manual).
Thanks

[Paul]

Good Luck....... If you happen to find one... maybe we can pass it around.

I've always had to rely upon a gas milage log, a note book of the changes and frequent reading of the spark plugs.... yep a royal pain....

I guess a dyno with an exhaust analyser would also do the trick....

[deaner]

I went to a "Bosch" service center once. They had one, it's seems to be used on other Bosch systems. (Not sure about how much of a need for this is now.) As L-jetronic is outdated. This was a awhile back. Mostly I've just tuned them to get a good idle and Co reading. Shouldn't be to hard to do. Nothing like seat of the pants tuning.

[opelnut_1]

stumbled upon this,

Bosch L-Jetronic idle adjustment, diagnostic and tune up article - ForoCoches

in my search for idle tunning

[wrench459]

Originally Posted by opelnut_1 stumbled upon this, Bosch L-Jetronic idle adjustment, diagnostic and tune up article - ForoCoches in my search for idle tunning

I love this part of the article


"""It's fairly easy to adjust the AFM to signal the ECU to send in a little more fuel. This mod gives a minor increase in power and better throttle response. It does not effect fuel economy but it can increase emissions. It's a simple reversible procedure. The AFM's door is held shut by spring pressure. We can reduce that spring pressure which will cause the door to open farther for a given amount of air volume. This will cause the AFM to signal the ECU for a little extra fuel. The procedure is simple. With the cover off look at the workings of the AFM and find the large wire shaped like a "W" and secured with a little bolt. That wire secures a gear and keeps the gear from turning. Mark the gear where it is secured by the wire (that's where my screwdriver is touching it in the photo below). Try to make the mark with a sharp knife so it will not wear off. Now hold the gear still and loosen the bolt securing the "W" shaped wire. Once the wire is free of the gear's teeth rotate the gear counter clockwise five or six teeth and secure it in that position by bolting the "W" shaped wire back into place. That's it! put the cover back on, secure it with silicone and you are done with the AFM."""


Thats how you clock the air flow meter wink wink

[wrench459]

Some questions
After the fuel rail theres a short hose what kind of clamp is on the injector inlet?
The ECM input connectors had corrosion problems they turned green.
The ..tps as we call it today was a simple idle or wot switch..they've might have been bent together.
Look close at the coolant temp sensor wiring is there a bulge in the wiring?
There might be a 210 ohm resistor lurking around.

[BQS4]

Originally Posted by wrench459 I love this part of the article """It's fairly easy to adjust the AFM to signal the ECU to send in a little more fuel. This mod gives a minor increase in power and better throttle response. It does not effect fuel economy but it can increase emissions. It's a simple reversible procedure. The AFM's door is held shut by spring pressure. We can reduce that spring pressure which will cause the door to open farther for a given amount of air volume. This will cause the AFM to signal the ECU for a little extra fuel. The procedure is simple. With the cover off look at the workings of the AFM and find the large wire shaped like a "W" and secured with a little bolt. That wire secures a gear and keeps the gear from turning. Mark the gear where it is secured by the wire (that's where my screwdriver is touching it in the photo below). Try to make the mark with a sharp knife so it will not wear off. Now hold the gear still and loosen the bolt securing the "W" shaped wire. Once the wire is free of the gear's teeth rotate the gear counter clockwise five or six teeth and secure it in that position by bolting the "W" shaped wire back into place. That's it! put the cover back on, secure it with silicone and you are done with the AFM.""" Thats how you clock the air flow meter wink wink

Dan;
Does this work for the Opels?

[wrench459]

Gene
Is there a black cover on your air flow meter?
The question that might needs to asked is how do you update a analog sensor?
Dan

[BQS4]

Originally Posted by wrench459 Gene Is there a black cover on your air flow meter? Dan

I think so.

[guyopel]

Gene
This is the same for the Opels .. I have the idle drop tool for your sys. and can show you how to adjust the air flow meter . HTH
John

[wrench459]

John

It looks like there might be a need on how to setup this old unit.
How about we hook up and make a article to upload.
I'm no expert on Opel F/I . But I was trained on the L-Jet Datsun's.

Dan

[Gary]

That would be a great article John and Dan.

Here's a link to the above article with pictures: L-Jetronic