D-Jetronic Bosch

IE23

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To put it nicely I have been handed scrabbled eggs.
so I need to do a full system health check/restore.

i have a manual for DS21, but is it the same for DS23 or is there another manual and does anyone know where I can obtain it?
 
The layout is the same, so the 21 manual will be adequate for testing parts. The ECU is a different number for early 21 (no trimpot), late 21 (trimpot) and for 23. The later cars also lost the third relay on the battery box and it was replaced by a shunt wrapped into the harness. The manual has the EFI information on pink pages and there is an additional page explaining the deletion of the third relay. There could be up to 6 relays on the side of the battery box for an EFI car with A/C. Later cars typically have the green plastic Sanor relays for the A/C and then the metal cased relays behind them for the EFI. The forward EFI relay is the control relay (Ignition control. Off coil.) and the 2nd relay is the pump relay (from ECU). If the 3rd relay is fitted, it relates to cold starting only.

The two pin connectors for the injectors and cold start injector have no polarity, so there is no need to worry about which way they connect. The plug will go into the cold start injector either way and it makes no difference. The thermotime switch on the side of the head controls the cold start injector and is an expensive part. The wiring diagram may seem initially confusing, but is fairly simple when you inderstand what it does. When it's cold, it earths one side of the cold start injector. There is a bimetallic strip inside that is also earthed and after a few seconds it heats up enough to break the earthing of the cirtucit to the cold start injector. So, the cold start injector may not operate at all if the engine is warm. You do need to be sure that the cold start injector works (easily tested) and also that the thermotime switch cuts it out.

If you are going to remove the injectors to test them, use a 3V supply. Polarity doesn't matter. The pressure regulator should hold to about 30psi.

The full load switch is just a vacuum operated switch, so see if it makes/breaks when applying a vacuum.
 
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Hi, not aware of a DS23 efi manual (doesn't mean there isn't) but as David S said, the DS21 injection manual should suffice as the principles are the same. Don't forget to also look up d jetronic troubleshooting on the net, you will find lots of information that porsche 914, Volvo and Mercedes owners have written up that is just as relevant to our djetronic system as it is there's.

The important thing is to firstly check the basics:

- Check for vacuum leaks, the djet system works by measuring vacuum in the intake manifold if you have a leak it won't operate correctly. As such if your valves are not correctly adjusted this will affect how the djet administers fuel, also worth doing a compression to ensure within spec.
- Ensure that your ignition system is operating correctly, timing correct?
- check that you have good grounds ( from the battery to the engine, and from the battery to the voltage regulator, also check the injection loom ground which goes to the same spot on the voltage regulator - other grounds are to the chassis under the spare wheel and also the ground by the fuel pump).

Also... Ensure you have corect fuel pressure, should be steady at 28psi.... Any fluctuation could mean a faulty pump, pressure regulator or blocked fuel filter... Disconnect the fuel pipe to the cold start injector and connect A fuel pressure gauge to this... If you can tape the gauge to the windscreen and drive around the block, you can then see what happens to the fuel pressure under load.

Good luck! I know what it's like to have a problem with the djet and I am still troubleshooting mine... It will be worth persevering in the end!
 
To put it nicely I have been handed scrabbled eggs.
so I need to do a full system health check/restore.

i have a manual for DS21, but is it the same for DS23 or is there another manual and does anyone know where I can obtain it?

Some good reading here Adrian, you can click on the individual components to get a better breakdown and understanding of what is what. . .
dssmpassion.fr/ds/injection.html - Translator

Cheers
Chris
 
I finally had time to get back to it. Its a process of elimination. The air control valve, which acts like a choke on a carby car, doesn't seem to be working. So I removed the air control unit, which was easier than I thought, once I moved the sphere out of the way.
Citroworld will restore this unit but I'm wondering if there is someone locally? Or am I best to send it to Citroworld?
Bosch part 280140030
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You can now buy the replacement wax element from, for example, Franzose, but you will need a lathe to remove the old one and to turn up a new base. It's a press fit. It can be done for a lot less than the exchange units if you are keen and have the tools.

Remove it from the housing with the water connections. Try cleaning the piston with carby cleaner, lubricate it and then see if it will move when placed in alternatively boiling and cold water. You may be lucky.
 
This is what I found; the mechanic did a repair job. The first picture shows you how an unbroken piece looks like and without internal blockages. The plastic T piece has subsequently broken again, so I propose a metal replacement as per picture.
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If you read the manual, the first thing mentioned 'Prerequisite is that the ignition system is in satisfactory condition'. So are you sure, 100% sure that the ignition system is 100%. Don't ask me how I know this.
 
If you read the manual, the first thing mentioned 'Prerequisite is that the ignition system is in satisfactory condition'. So are you sure, 100% sure that the ignition system is 100%. Don't ask me how I know this.

Not 100% sure of anything at the moment. I'm starting with picking the low hanging fruit. The air control valve doesn't work under test with boiling water. So first step. Second step is to address the vacuum blockage (created by the mechanic) and possible vacuum leaks from hard and cracked vacuum hoses and improve the joins.
 
That Y-piece looks like it would have had a reduced air flow and it would be on the air filter side, presumably for the throttle bypass, rather than part of the vacuum piping. The manifold vacuum is for the manifold pressure sensor, full load switch and a dashpot unit that is part of the throttle body. The vacuum pipes need to be good as the heart of D-Jet is the pressure sensor.
 
Anyone know if or where I can purchase the long vacuum hoses from? The set that run over the top of the inlet manifold are shaped to fit.
 
Really, they're shaped to fit? You'd think they just end up that shape from being draped over the manifold?
 
That's a shame, suddenly the options have narrowed..... I have checked Citrotech and Citroworld, no luck, perhaps Darrin at Citroen Classics can help. Otherwise Ets Jean Blondeau

FYI
How to Order


By phone at 01 42 87 90 07
(Tuesday to Friday from 9:00 to 1:00 p.m. and 5:00 p.m. to 7:00 p.m. , Saturday from 9:00 to 12:00 )
By fax 01 42 87 72 44
By email ( ids@nfp-france.com ) by using our contact form or from the store (open Tuesday morning to Saturday morning from 9am to 12pm and from 14h to 18h30).


The necessary information


To enable us to serve you better, remember to bring the following information about your car:


Vehicle Model: DS or ID, DSpecial, DSuper, SM, HY ...
month and year of the first movement of the vehicle
Mine Type
Fiscal power (11, 12, or 13 HP)
mechanical gear box, hydraulic or automatic
carburetor or injection engine
Pallas Pallas or not
sedan, station wagon or convertible
Methods of payment:


We accept the following means of payment


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against refunding (supplement of € 8.37 including tax)
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Anyone know if or where I can purchase the long vacuum hoses from? The set that run over the top of the inlet manifold are shaped to fit.

Head upto pirtek or similar. I would think any hose of the right diameter that you can form a 90 degree bend in will suffice. they will most likely only have pressure hose, so it won't compress under vacuum as it'll have webbing it it to increase it's strength.

I'm not convinced this is your issue. Surely you can block off completely the aux-air regulator and get the existing hoses leak free enough to see if it runs correctly when warm :confused:

seeya,
Shane L.
 
The project continues; Had no luck finding original parts so I took Shane's advice (only option) to make up my own set of hoses and fittings. I changed the brass fittings to T shape because they line up the direction of the hoses better. The brash fittings are really too fat for the hoses but with boiling water and a lot of pushing and squeezing and tired muscles they eventually go on. Not sure if it makes any difference but I was very careful to maintain the original Internal Diameter measurement of the fittings & connections to avoid any change in air flow.

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