Attention: TDR Forum Junkies 
This is also posted in an existing thread, but buried, and may not get any attention - so let's try this...
Since we've now heard from at least several guys experiencing problems when rapid accelleration, then sudden letting off the pedal is involved - and at least one of those apparently resulting in a VP-44 failure - I have a question that maybe one of the experts can respond to:
We are told the actual timing of fuel flow from the VP-44 is controlled by the ECM thru the fuel solenoids inside the VP-44 (at least I guess that's where they're located). In this scenario, I assume the fuel solenoids function much like the valves in a combustion chamber - and the ECM is essentially the "camshaft" that controls that opening/closing and timing...
BUT, what if the timing or rate of solenoid operation is off - either by faulty programming or other factors that create a situation where the injector pump piston tries to force it's load of fuel out in a normal fashion, but the delivery-side solenoid refuses to open, creating a hydro-lock situation? Is that possible with these pumps, or is there a built-in override outlet fuel path to prevent the certain destruction of the pump that would otherwise occur?
Further, is it possible that some of the add-on boxes we use might aggravate the above scenarion even further - since it seems all the guys so far affected were using power boxes?
Comments?
Since we've now heard from at least several guys experiencing problems when rapid accelleration, then sudden letting off the pedal is involved - and at least one of those apparently resulting in a VP-44 failure - I have a question that maybe one of the experts can respond to:
We are told the actual timing of fuel flow from the VP-44 is controlled by the ECM thru the fuel solenoids inside the VP-44 (at least I guess that's where they're located). In this scenario, I assume the fuel solenoids function much like the valves in a combustion chamber - and the ECM is essentially the "camshaft" that controls that opening/closing and timing...
BUT, what if the timing or rate of solenoid operation is off - either by faulty programming or other factors that create a situation where the injector pump piston tries to force it's load of fuel out in a normal fashion, but the delivery-side solenoid refuses to open, creating a hydro-lock situation? Is that possible with these pumps, or is there a built-in override outlet fuel path to prevent the certain destruction of the pump that would otherwise occur?
Further, is it possible that some of the add-on boxes we use might aggravate the above scenarion even further - since it seems all the guys so far affected were using power boxes?
Comments?
