Jump to content
Do Not Sell My Personal Information

Injectors offset learning at max limit?


Mhamill66
 Share

Recommended Posts

Hi, 

I have hooked my focus up to the computer and got back the following message for 3 injectors 'injectors offset learning at max limit'. 

 

Any ideas what that means? Is that 3 injectors that need replacing? Or 4 injectors that need reprogramming? 

 

Thank you, 

Mike.

IMG-20200610-WA0001.jpg

  • Like 1
Link to comment
Share on other sites


Those 3 are now worn so much that the ECU can no longer compensate.

It's not worth the cost of replacing them unless you're having noticeable issues with running or excess smoke.

Link to comment
Share on other sites

Thank you for the reply. 

 

I get white smoke when in first start the car, followed by maybe 10 seconds of 'jutters' from the engine. Then the car is fine. I have been advised to have them reprogrammed at ford to level out the fuel intake. Hopefully they wont charge an arm and a leg. 

Link to comment
Share on other sites

Reprogramming worn fuel injectors does not make any sense and is a waste of time and money.

Fuel injectors of a modern common rail diesel engine are high precision parts that are produced within very small tolerances. Despite the very small tolerances no single fuel injector is identical. After production every single fuel injector is bench tested and compared with a predefined base value. The deviation of the actual test results to the predefined base value is converted into a hexadecimal correction factor value that is (usually) printed onto the fuel injector.

By programming the fuel injector correction factor values into the PCM the PCM "knows" the exact deviation of each fuel injector to the predefined base value. Based on this information the PCM is capable to adapt the injection timing and duration to achieve optimum performance. During time the PCM adapts itself and compensates for normal wear of the fuel injectors. If the fuel injectors are worn too much the PCM is no longer able to compensate and generates a DTC code for the particular fuel injector.


If the injector is worn the hexadecimal code that is printed on the fuel injector does no longer match the actual state of the fuel injector. When reprogramming the PCM using the values on the fuel injector there is a high risk that the engine runs even worse than before. In some cases the engine may not run at all.

 

  • Like 3
Link to comment
Share on other sites

However, white smoke isn't right, and means unburnt diesel, so you could possibly have one or more injector overfuelling. This isn't necessarily connected with your original query, best take 'em to a diesel specialist for testing, if you can remove' em yourself it costs around £15 each for testing in a proper test rig, NOT to be confused with a simple leak-off test. 

Link to comment
Share on other sites


10 seconds of jitters and white smoke on startup really isn't worth replacing injectors for.  We already know they're worn...just not enough to be worth fixing yet. 

The injectors on this engine (8v DV6) are utter rubbish, it's not uncommon for all 4 to have been replaced within the warranty period!  That's the nature of modern piezo injectors though...and is the price we have to pay for the extra accuracy and precision that they provide...or provided when new at least! :rolleyes: 

  • Like 2
Link to comment
Share on other sites

Latest Deals

Ford UK Shop for genuine Ford parts & accessories

Disclaimer: As the club is an eBay Partner, The club may be compensated if you make a purchase via the club

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share






×
×
  • Create New...

Forums


News


Membership


  • Insurance
  • Support