Common rail diesel injector coding question

[datman]

With common rail diesels being some 25 years old in some cases maybe someone on here might know about codes, i was wondering if there was a way to decode the trim / compensation codes to actually give a numerical amount by which the injector is offset, assuming this is just one number, in that way different injectors might be compared etc. Thanks

[welshpug]

Thats a question for somewhere like PF Jones that supply a lot of rebuilt/refurbished commonrail injectors, pretty sure they give the injectors a new code.

Not sure why you would need the specific number, as you don't need it, just enter the code off the injector into the ecu with the appropriate diagnostic tool.

[raumer]

My experience (used to develop the trim strategies and develop new injectors etc....) was that the codes should be quite difficult to decode without an injector test rig. The codes are multipart. Earlier systems have 2 or 3 codes, most complicated one I know of currently has about 50 codes. Depending on the injector manufacturer depends on what the codes do and how well they do it.

There is a table of codes in each ECU so in theory you could work it out if you know your way around software well enough. This is probably the easiest way of doing it.

Or you can run the injectors on a test rig, enter different codes and see how it changes the signal (length and timing). This way you could map out all of the codes and back calculate the nominal injector performance.

There may be another way of working it out but I always had the luxury of knowing all the details so didn't have to worry about reverse engineering it.

Alternatively if you are a reconditioner you may be able to get the manufacturer to supply the data you need.

That's the short version but hopefully helps a bit.

[datman]

THanks. I was having trouble coding in a reconditioned injector, (with code issued by the company) so i was wondering if it was possible to 'see' if it was ok to drive it not coded, and knowing how much it differed in performance to the stored injector code. It runs ok.

[raumer]

Especially for early coded systems the injectors had to pass certain gates before they could be coded. Therefore they should be reasonably close anyway. Most of the time running without codes or on the previous code is worth trying. Might not be exact on emissions etc... but you can soon tell if it is running right.

[datman]

A friend came over with this Autel scan tool and that coded it ok. Still no way of knowing how far off it was .