Bulletins & Advisories i-DTEC Fuel System Priming

Discussion in 'Technical Articles' started by Ichiban, Sunday 1st Jan, 2012.

  1. Ichiban Founder Staff Team

    England CJ Leeds
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    The information applies to 09~10MY Accord and 10YM CR-V diesel which are now fitted with piezoelectric injectors. If you experience difficulties in starting a vehicle and you suspect it has been run out of fuel or has been miss fuelled, it may be due to air in the high pressure fuel system. The fuel system is designed to be self priming from a presupply pump located in the fuel tank. This pump will supply and prime the fuel system up to the high pressure fuel rail. When the fuel has been drained or has run out there may be a PGM-FI symbol on the multi function display. In such cases a priming cycle should be followed before cranking the
    engine.


    Before commencing the priming process the tank should have been refuelled with a minimum of 5 litres of diesel fuel. With the ignition in position 2 the presupply pump will be heard in the back of the vehicle pumping fuel to the engine. This pumping cycle will last 40 seconds before the presupply pump is disabled automatically (to prevent damage), unless the engine is cranked during this period. You should allow 30 seconds to prime after refilling before cranking the engine for the first time, cranking should be kept to 10 seconds at a time (max) to prevent damage to the starter and fuel pump. If the engine fails to start, restart the 30 second priming cycle and attempt cranking again. At this point the high pressure rail and rail target pressures can be monitored on HDS. In such cases the indicated target rail pressure (30 Mpa) should be achieved during or just after the second attempt at cranking the engine.

    If the target pressure is not being achieved check for leaks on the high pressure system, DO NOT crank the engine during this check. If there are no leaks suspect that either the high pressure fuel pump is being starved of fuel or that it requires replacement.In cases where the target pressure is being achieved but the engine will still not start, replace all four injectors with known good ones and retest. If the engine then starts the original injectors will normally require replacement. This might happen when the vehicle has run out of fuel, this is caused by air contaminating the hydraulic amplifier within the injectors, rendering them inoperative.

    The current fuel priming system is unable to overcome this condition and would normally require new injectors.
    However this condition may be over come by either fitting one inoperative injector at a time to a donor vehicle or fitting 3 good injectors to the subject vehicle and fitting the inoperative injectors one at a time, remembering to enter correct IQA data at each swap.

    In each situation the engine will initially start on three cylinders but will force the inoperative injector to function after a few seconds. The operation of the subject injector should be monitored on HDS and given 10-15 minutes running time to purge all air from the injector. Ensure that injector calibration adjustment is within service limits before moving on to the next injector.Once successfully completed re-install injectors to the subject vehicle and test, ensure that all 'one use only parts' that have been removed have been replaced with new items (high pressure pipes and gaskets). Gaskets should be replaced each time an injector is installed. Note: New injectors are supplied in a pre-primed condition.
     
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  2. Paul Expert Advisor ★ ★ ★ ★ ★

    Very interested. Quite amazing that running out of fuel can effectively kill the injectors. But with the addition of 3 good injectors you can resurrect the previously dead one. I'm sure a lot of dealers who aren't aware of this would simply replace all four injectors at a massive cost.
     
  3. Ichiban Founder Staff Team

    England CJ Leeds
    30,133
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    Dealers are aware of this buddy their bible on the I-DTEC is FANTASTIC there isnt a scenario which isnt cover ..
     
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