markomate2
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Quick update, or more, probably useless, info!
Ive been looking into the coding structure for the TD5 injectors.
As you all probably know, the TD5 uses an EUI injector system, Electronic Unit Injectors mean you dont have a separate injector pump or high pressure common rail.
There is a common fuel gallery built into the head but its only 60 odd psi, as opposed to a true common rail system that can work at around 44,000 psi!
The extra cam lobe on the camshaft acting on the injector via the rocker, generates the high pressure directly inside the injector, on an EU3 TD5 its around 36,000 psi.
When the injectors are built, the TD5,s are by Delphi, they are calibrated and a five letter code is generated which is printed on top of the EUI.
This is the code which must be programmed into the ECU, it ensures the ECU knows the individual characteristics of each injector thus allowing the engine to run properly over the entire rev range.
As my injectors have been rebuilt, the original codes are now invalid, so Ive been trying to find out if I can, for the want of a better word, "hack" the coding system, so I can find out what the codes actually mean, I finally tracked down a bit more info as follows:
The following came from a Delphi paper about their newer injectors (E3) but I think it applies to the older (E1, E2) units as well.
Five letter EUI code: "AABBC" (any combination of letter in two pairs and a single letter is possible)
First pair "AA" Response time, start of injection
Second pair "BB" Response time, end of injection
Last letter "C" Variance in idle performance
Typical codes we see could be "MNDGJ" etc
The interesting bit is that the letter pairs are random, MN is not better or worse than NQ, this was to stop "deliberate overfueling" or tweeking of the performance by simply upping the letter values.
So the bottom line is, no you cant make up your own codes! Phew that was a bit long!
Anyway in my case its irrelevant as my issues are nothing to do with codes! But something more fundamental.
Info from Delphi site and other papers!
Anymore info on the above including "what the hell are you talking about" welcome.
Mark
Ive been looking into the coding structure for the TD5 injectors.
As you all probably know, the TD5 uses an EUI injector system, Electronic Unit Injectors mean you dont have a separate injector pump or high pressure common rail.
There is a common fuel gallery built into the head but its only 60 odd psi, as opposed to a true common rail system that can work at around 44,000 psi!
The extra cam lobe on the camshaft acting on the injector via the rocker, generates the high pressure directly inside the injector, on an EU3 TD5 its around 36,000 psi.
When the injectors are built, the TD5,s are by Delphi, they are calibrated and a five letter code is generated which is printed on top of the EUI.
This is the code which must be programmed into the ECU, it ensures the ECU knows the individual characteristics of each injector thus allowing the engine to run properly over the entire rev range.
As my injectors have been rebuilt, the original codes are now invalid, so Ive been trying to find out if I can, for the want of a better word, "hack" the coding system, so I can find out what the codes actually mean, I finally tracked down a bit more info as follows:
The following came from a Delphi paper about their newer injectors (E3) but I think it applies to the older (E1, E2) units as well.
Five letter EUI code: "AABBC" (any combination of letter in two pairs and a single letter is possible)
First pair "AA" Response time, start of injection
Second pair "BB" Response time, end of injection
Last letter "C" Variance in idle performance
Typical codes we see could be "MNDGJ" etc
The interesting bit is that the letter pairs are random, MN is not better or worse than NQ, this was to stop "deliberate overfueling" or tweeking of the performance by simply upping the letter values.
So the bottom line is, no you cant make up your own codes! Phew that was a bit long!
Anyway in my case its irrelevant as my issues are nothing to do with codes! But something more fundamental.
Info from Delphi site and other papers!
Anymore info on the above including "what the hell are you talking about" welcome.
Mark