PGM-FI System is SEQUENTIAL

[Grin0048]

Yes, yes heaven forbid someone try to clear up an erroneous concept concerning 4th gen Accords. Besides, I already admitted that I was wrong about ALL fuel injection systems being sequential. That's more than most here will do if they are clearly wrong.

Besides, I can't be banned, I'm 73 and can say anything I want to.

I posted in the other thread assuming that the person who said these engines aren't sequential was right (should know better than that)...the problem with what you said in the thread (and this one) is the implication that a simultaneous injection system is somehow preposterous.

[cvandulken]

MY EXPERIENCE:

i've taken the dizzy off the engine(obd0 and 1) while still connected to electrical, set key to acc/run and spun it by hand to listen for injector activity, definitly seq multi port....not batch, or dual point. dont forget to disconnect fuel pump when doing this.

they've been doing this on honda's i've worked on as early as 86 that feature mfpi as opposed to the civics dpfi (dual point fuel injection). instead of having a log style intake, it looks like a carb instead 2 fuel injectors in the side of the down draft throttle body. ( for those who dont know )

check out the 1.5l 1990 civic non si model, they all pretty much run dpfi in those years.. 92+ they went to mfpi on the eg chassis 1.5l and pretty much anything after that was mfpi on any model.

[honda_kid]

I haven't seen anything here that would require anything that drastic. It's just a discussion. No flaming or name calling or anything like that.

. . . yet

[owequitit]

One of the things that made PGM-FI such a break through in the first place was that it was one of the first electronically operated and optimized sequential fuel injection systems offered on the market.

Many others were still using mechanical fuel injection, or batch fired fuel injection systems. Some high end cars had already implemented sequential systems, but Hondas was one of the best at that time, and it was much more accessible price wise. It was one of the tools that allowed Honda to squeeze more efficiency out of their engines relative to everyone else.

They did dabble in what amounted to throttle body injection (DPFI), but they fairly quickly had made the transition to all sequential MPFI, and were a leader in that regard. Many companies continued to use TBI or batch fire injection for sometime after.

For the record, the last DPI Honda I can think of was the 1991 Civic, and everything after that was all PGM-FI.

[93accordfreak]

I'm glad this was cleared up. I was doubting myself a bit after reading the post in that other thread.

Good read here so far.

[bcjammerx]

coulda sworn when i looked at the wiring diagram a while back the injectors all shared power and ground...but they do not. Each have a separate ground through the ecu...thus...sequential...or at least the potential for sequential.

http://smash.systemsabuse.com/HaynesWiringDiagrams.pdf

around b-11

coolness

[accordztech]

my 86 300zx nissan is group fire 1,3,5 and then 2,4,6 but after 3k rpms it turns into batch fire in pairs...not really efficient.

[dano28]

coulda sworn when i looked at the wiring diagram a while back the injectors all shared power and ground...but they do not. Each have a separate ground through the ecu...thus...sequential...or at least the potential for sequential.

Ok..by looking at the wiring diagram you see there is the POTENTIAL for sequential fuel injection. But you are still not sure if PGM-FI actually is sequential or not ?

What do you need as proof ??