Hi World
Will a D Jet ECU for a 2 Liter work for a 1.7 Liter Also dJet?
Thanks
Full Version: D-Jet ECU
It may on some '72-'73 cars. Verify here by part #
https://members.rennlist.com/pbanders/DJetParts.htm
https://members.rennlist.com/pbanders/DJetParts.htm
You should be able to get the correct one for ~ $50
I have a complete 1.7 (?) D-jet setup that I am putting up for sale in the classifieds.
This is the ECU for it.
Click to view attachment
Click to view attachment
This is the ECU for it.
Click to view attachment
Click to view attachment
Not a very good idea to mix and match D-Jet parts.
I would call the D-Jet system a comparative system. There is no real feedback to the ECU from any sensors.
All the ECU does is take in signals from the sensors and compare those to on board pre-programmed data, all in analog form.
Example the head temp sensor, it's resistance is compared to an on board resistance and the increase or decrease changes the pulse length of the injectors.
Mixing the components will cause tuning problems and fuel consumption issues.
The Bosch engineers used real data to set up the D-Jet ECU, but not until the introduction of stuff like the O2 sensor did the engine start telling the ECU what might be happening.
Once you have assembled the correct collection of parts for a particular "year" than you will be able to tune the system making predictable adjustments.
All of the parts necessary for a complete system are available, there were thousands of D-Jets made and some more desirable items may cost more and others cheap and abundant.
I would call the D-Jet system a comparative system. There is no real feedback to the ECU from any sensors.
All the ECU does is take in signals from the sensors and compare those to on board pre-programmed data, all in analog form.
Example the head temp sensor, it's resistance is compared to an on board resistance and the increase or decrease changes the pulse length of the injectors.
Mixing the components will cause tuning problems and fuel consumption issues.
The Bosch engineers used real data to set up the D-Jet ECU, but not until the introduction of stuff like the O2 sensor did the engine start telling the ECU what might be happening.
Once you have assembled the correct collection of parts for a particular "year" than you will be able to tune the system making predictable adjustments.
All of the parts necessary for a complete system are available, there were thousands of D-Jets made and some more desirable items may cost more and others cheap and abundant.
The above post is confusing. This statement is not true that "There is no real feedback to the ECU from any sensors."
D-Jet is an "open loop" FI system, receives data (feedback) from its sensors and calculates pulse width to match demand based on that data. A "closed loop" system includes an O2 sensor(s) which additionally monitors exhaust gas characteristics to match demand and is more advanced than D-Jet.
D-Jet cannot really be and is not intended to be 'tuned' per se. The components are 'fixed' to the average owner - its Plug N Play only - so the statement "Once you have assembled the correct collection of parts for a particular "year" than you will be able to tune the system making predictable adjustments" is also not a good characterization. The beauty of D-Jet is its simplicity and that as long as individual components, which can be individually tested, are good, the system works. No 'tune-ups' or alignments adjustments are needed other than the basic engine mechanical, fuel pressure, idle mixture and air mixture settings.
D-Jet is an "open loop" FI system, receives data (feedback) from its sensors and calculates pulse width to match demand based on that data. A "closed loop" system includes an O2 sensor(s) which additionally monitors exhaust gas characteristics to match demand and is more advanced than D-Jet.
D-Jet cannot really be and is not intended to be 'tuned' per se. The components are 'fixed' to the average owner - its Plug N Play only - so the statement "Once you have assembled the correct collection of parts for a particular "year" than you will be able to tune the system making predictable adjustments" is also not a good characterization. The beauty of D-Jet is its simplicity and that as long as individual components, which can be individually tested, are good, the system works. No 'tune-ups' or alignments adjustments are needed other than the basic engine mechanical, fuel pressure, idle mixture and air mixture settings.
QUOTE(Jeff Bowlsby @ Apr 17 2018, 04:12 PM) 
The above post is confusing. This statement is not true that "There is no real feedback to the ECU from any sensors."
D-Jet is an "open loop" FI system, receives data (feedback) from its sensors and calculates pulse width to match demand based on that data. A "closed loop" system includes an O2 sensor(s) which additionally monitors exhaust gas characteristics to match demand and is more advanced than D-Jet.
D-Jet cannot really be and is not intended to be 'tuned' per se. The components are 'fixed' to the average owner - its Plug N Play only - so the statement "Once you have assembled the correct collection of parts for a particular "year" than you will be able to tune the system making predictable adjustments" is also not a good characterization. The beauty of D-Jet is its simplicity and that as long as individual components, which can be individually tested, are good, the system works. No 'tune-ups' or alignments adjustments are needed other than the basic engine mechanical, fuel pressure, idle mixture and air mixture settings.
Except if you modify your engine, but who does that!
You are mistaking feed for "feedbacK" the sensors only feed info to the ecu, no date is feed back to the unit for modification of the signal, as you say it is basic but it can be "modified"or tuned for a specific engine.
My car is a 71. 1.7. I did find my ecu was not working correctly by using a 74. 2.0 ecu.I would like to know if I should try to source the original 1.7 ecu without the idle enrichment knob or get one like the one I used to find my part was bad? Thanks Bobco
If this will work for you i have it available.
http://www.914world.com/bbs2/index.php?sho...=313564&hl=
Chris
http://www.914world.com/bbs2/index.php?sho...=313564&hl=
Chris
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