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what are the differences between the different types of fuel injection systems?

I would want to find out how the distribution works in modern fuel injection systems.

Public Comments

1. TBI = THROTTLE BODY INJECTION =ONE OR TWO LARGE INJECTOR/S FOR ALL CYLINDERS TPI = TUNED PORT INJECTION = ONE INJECTOR FOR EACH CYLINDER AT THE INTAKE PORT...FUEL IS UNDER PRESSURE AND ALLOWED TO ENTER THE INTAKE PORT WHEN AN ELECTRIC PULSE ACTIVATES THE INJECTOR ... THE ADVANTAGE TO A TUNED PORT INJECTION IS MORE ACCURATE FUEL DELIVERY DUE TO THE CLOSNESS OF THE INJECTOR TO THE CYLINDER
2. On automobiles they had the "TBI" system first which was basically a carburator with fuel injectors. They then modified it to a "TPI" which is the current fuel injection system in operation. Diesels work on the "TPI" therory with a distribution pump.
3. i own a repair shop,and i,ll try and explain it,there are 2 types of it,,throttle body fuel injection, which is like having a carburetor ,but it has only 2 injectors in it ,and it sprays a mist of gas every-time the computer tells it too in to the engine and this fires the engine when it mixes and enters the combustion chamber,, then there's multi port fuel injection,it has a separate injector for each cylinder on the vehicle,and its more complex to deal with and uses a different computer system all together ,,it sprays a mist of gas upon demand from various sensors that tell it when the engine needs it ,and it like the other type measures the amount each time it is sprayed in to the engine,so it only gets what it needs to fire good,this help,s prevent flooding and excess fuel usage on any vehicle,and all of this is done in a 1/10th of a second,,but its done many hundreds of times per minute to keep the engine running,its a pretty neat little system when you break it down and really see how it really works,,good luck i hope this help,s.
4. all of these are good answers, and most diff. manufacturers use diff. names for similar systems. the one more type would be commonly called direct injection systems, used on diesels. the fuel is injected direcly into the combustion chamber at precisely the right time under ultra hi pressure. in the case of the new vw/audi tdi/pd engines, the injecters themselves produce 29,000 psi. yes, i said 29thousand.
5. Just to straighten the diesel system out. They use a direct injection system now, straight into the cylinder.
6. ok what ur talking about is batch or sequential fuel injection. on the first multi port injector systems they fired all injectors at one bank at the same time for the same length of time meaning if u had a v6 gm for instance 1-3-5 on one side 2-4-6 on the other when 1 hit tdc the program would fire 1-3-5 all at the same time for the same length of time thats called batch fire used til approx 94. now the thing is ull see on alot of engines they will say SFI meaning sequential fuel injection basically at predetermined times in the program based on timing from either a crank or cam sensor it fires each individual injector when its supposed to i think that is what u want to know. the injector itself is a electric solenoid with a pintle. fired in millisecond increments. otherwise fuel distribution is even simpler as most injected systems all injectors are connected to one rail with a pressure and a return line attached at each end with a regulator in line to control pressure usually controlled by engine vacuum hope this helps