Honda Car Forum

TeGGeR® wrote:
> Matt Ion <soundy@moltenimage.com> wrote in
> news:CtlFg.431985$IK3.362769@pd7tw1no:
>
>
>>Oh, and... power readings at the injectors were tested with meter
>>grounded to battery, block, and body, at different times (whichever
>>was most handy for that particular instance).
>>
>
>
>
> Did ANYBODY attempt the particular procedure I prescribed? (To answer my
> own question: evidently not.)

I don't know if he tried any of the ECU readings. First thing I did when I got
there was test for the injector power, since he already had the meter out, and
noticed the excessive voltage drop... and proceeded to find the source of that.

Jim Yanik wrote:
> Matt Ion <soundy@moltenimage.com> wrote in
> news:ehoFg.422243$iF6.226183@pd7tw2no:
>
>
>>Jim Yanik wrote:
>>
>>>Matt Ion <soundy@moltenimage.com> wrote in
>>>news:PXcFg.419370$Mn5.171051@pd7tw3no:
>>>
>>>
>>>
>>>>TeGGeR® wrote:
>>>>
>>>>
>>>>>Matt Ion <soundy@moltenimage.com> wrote in
>>>>>news:v3REg.410737$iF6.53449@pd7tw2no:
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>TeGGeR® wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>>Matt Ion <soundy@moltenimage.com> wrote in
>>>>>>>news:vINEg.420523$IK3.280117@pd7tw1no:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>He's GOT a Haynes manual for this thing, which he can't find...
>>>>>>>>i'm SO much more useful with a good wiring schematic in front of
>>>>>>>>me
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>Click Auto Repair Reference Center from the menu at left.
>>>>>>>Navigate to your car. There are wiring diagrams.
>>>>>>
>>>>>>Sweet, thanks!
>>>>>>
>>>>>>Meanwhile... he's determined there's no power to the injectors.
>>>>>>Ground is good, but no signal into them. Waiting to see if he'll
>>>>>>actually bother to check the ECM codes (I sent him the link from
>>>>>>your FAQ).
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>Power to the injectors is from the line that comes from Terminal 7
>>>>>of the Main Relay. The fuel pump and the injectors receive power
>>>>
>>>>>from the same basic source, so the trouble is probably a
>>>>
>>>>>disconnected wire between the Main Relay and the injector harness.
>>>>
>>>>Well, I actually got my hands on the car this afternoon and, with the
>>>>help of the schematic (you ARE the man!), I think I found the source
>>>>of the problem: the fuel pump is for some reason sinking TONS of
>>>>current and causing the voltage throughout the car to drop
>>>>excessively.
>>>>
>>>>Specifically: checking voltage at the injectors, I get only about
>>>>8.5V while they're activated, and closer to 5.5V when cranking.
>>>>Voltage *at the battery* drops from about 12V to just barely over 8V
>>>>for a few seconds as soon as the key is switched to Ignition, then
>>>>jumps back up to 12V, nicely coinciding with the brief time the main
>>>>relay switches on the pump and injectors. Connecting jumper cables to
>>>>my running car, thus providing 14V to the system, allowed the car to
>>>>ALMOST start as system voltage dropped to about 9.5V with ignition
>>>>on, and 8.5V while cranking - it tried to catch a few times, but just
>>>>couldn't quite fire up.
>>>>
>>>>After a little more tracing, I ruled out the injectors and internal
>>>>wiring problems... looking at the schematic, there are only three
>>>>things on that circuit - the two injectors and the fuel pump - so I
>>>>figured either there was a "near-short" somewhere in its wire (a dead
>>>>short would have blown the fuse), or the pump was having issues... as
>>>>it turned out, unplugging the pump lead got rid of the strange
>>>>voltage drop.
>>>>
>>>>So I'm thinking the pump probably has bad bearings or sleeves, or is
>>>>badly gummed up, or in some other way is being prevented from turning
>>>>freely, and thus is drawing excessive current, enough to drop the
>>>>system voltage too low to operate the ECM and/or injectors, but not
>>>>enough to pop the related fuse.
>>>>
>>>>Lordco was closed by this time, so my buddy's gonna pick up a new
>>>>fuel pump tomorrow... but he'll be installing it on his own, as I'll
>>>>be down at the football game!
>>>>
>>>>Hopefully that takes care of things... I'll let you know!
>>>>
>>>
>>>
>>>It might be just a clogged fuel pickup.
>>
>>If that was the case, there'd be no pressure on the pump and it would
>>spin freely; it wouldn't be drawing a ton of current.
>>
>
>
> No,a pump trying to pull on a clogged line draws more current.
> It spins freer under normal loads.Simple hydraulics.

If it can't pull any liquid in, there's nothing to offer resistance to the pump,
is tehre?

Besides, the pump is out now, and the intake filter is clean.

TeGGeR® wrote:
> Matt Ion <soundy@moltenimage.com> wrote in
> news:PXcFg.419370$Mn5.171051@pd7tw3no:
>
>
>
>>Hopefully that takes care of things... I'll let you know!
>
>
>
>
> Matt, hold off until you know for sure that this is the issue. Posting
> as-it-happens is an invitation to severe -- and likely inaccurate --
> speculation.

Well, anyone who cares to speculate wildly and make fools of themselves are
welcome to do so...

> Your thesis is intriguing. I await the synthesis, empirically arrived at,
> of course...

Buddy picked up another fuel pump from an '89 Civic but it proved to not fit the
tank - the assembly projects straight down from the mounting plate, rather than
on an angle like the one that came out, and hits the bottom of the tank. Back to
the wrecker...

Okay, quick update... new fuel pump in, took care of the voltage drop
problem... now we're getting an ALMOST-start. It cranks, it tries to
catch, it won't quite take off.

ECU gives a code 16 ("Fuel Injector System: defective circuit or
unplugged / defective fuel injector".)

Both injectors appear to work when independently powered. Both
injectors seem to click while cranking. Looking down the TB throat,
there's definitely gas being fed in from the main injector - hard to
tell if the aux injector is doing anything. Holding the choke open
manually helps a bit, but it still won't quite "catch".

Lots of spark on all cylinders... firing order is correct as far as
I've been able to determine without having found the EXACT manual for
this specific car (1-3-4-2 clockwise from the bottom-left when looking
straight at the top of the distributor cap). Getting regular "puffs"
from the exhaust so there seems to be steady compression from all
cylinders.

Odd thing is, the plugs appear dry when I pull them out, so they're
either firing or not getting any air/fuel mix, which doesn't make any
sense unless the intake valves aren't working... and if that was the
case I'd think I wouldn't get the "puffs" out the exhaust, if it wasn't
drawing in any air.

So near, yet so far away... *sigh*



Matt Ion wrote:
> TeGGeR® wrote:
> > Matt Ion <soundy@moltenimage.com> wrote in
> > news:PXcFg.419370$Mn5.171051@pd7tw3no:
> >
> >
> >
> >>Hopefully that takes care of things... I'll let you know!
> >
> >
> >
> >
> > Matt, hold off until you know for sure that this is the issue. Posting
> > as-it-happens is an invitation to severe -- and likely inaccurate --
> > speculation.
>
> Well, anyone who cares to speculate wildly and make fools of themselves are
> welcome to do so...
>
> > Your thesis is intriguing. I await the synthesis, empirically arrived at,
> > of course...
>
> Buddy picked up another fuel pump from an '89 Civic but it proved to not fit the
> tank - the assembly projects straight down from the mounting plate, rather than
> on an angle like the one that came out, and hits the bottom of the tank. Back to
> the wrecker...

soundy@moltenimage.com wrote in
news:1156033205.645620.308870@b28g2000cwb.googlegr oups.com:

> Okay, quick update... new fuel pump in, took care of the voltage drop
> problem... now we're getting an ALMOST-start. It cranks, it tries to
> catch, it won't quite take off.
>
> ECU gives a code 16 ("Fuel Injector System: defective circuit or
> unplugged / defective fuel injector".)



Wanna take a second look at that Main Relay?

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

TeGGeR® wrote:
> soundy@moltenimage.com wrote in
> news:1156033205.645620.308870@b28g2000cwb.googlegr oups.com:
>
>> Okay, quick update... new fuel pump in, took care of the voltage drop
>> problem... now we're getting an ALMOST-start. It cranks, it tries to
>> catch, it won't quite take off.
>>
>> ECU gives a code 16 ("Fuel Injector System: defective circuit or
>> unplugged / defective fuel injector".)
>
>
>
> Wanna take a second look at that Main Relay?
>
yeah, no kidding...

TeGGeR® wrote:
> soundy@moltenimage.com wrote in
> news:1156033205.645620.308870@b28g2000cwb.googlegr oups.com:
>
>
>>Okay, quick update... new fuel pump in, took care of the voltage drop
>>problem... now we're getting an ALMOST-start. It cranks, it tries to
>>catch, it won't quite take off.
>>
>>ECU gives a code 16 ("Fuel Injector System: defective circuit or
>>unplugged / defective fuel injector".)
>
>
>
>
> Wanna take a second look at that Main Relay?

Already did. All working fine. Came out of another working Civic, in fact.

Like I said, the injectors ARE working, they ARE spraying fuel (at least, the
main injector is).

jim beam wrote:
> TeGGeR® wrote:
>
>> soundy@moltenimage.com wrote in
>> news:1156033205.645620.308870@b28g2000cwb.googlegr oups.com:
>>
>>> Okay, quick update... new fuel pump in, took care of the voltage drop
>>> problem... now we're getting an ALMOST-start. It cranks, it tries to
>>> catch, it won't quite take off.
>>>
>>> ECU gives a code 16 ("Fuel Injector System: defective circuit or
>>> unplugged / defective fuel injector".)
>>
>>
>>
>>
>> Wanna take a second look at that Main Relay?
>>
> yeah, no kidding...

Do you have anything useful to add, or are you just here to be a nob?

Matt Ion <soundy@moltenimage.com> wrote in
news:mJaGg.440318$IK3.223342@pd7tw1no:

> TeGGeR® wrote:
>> soundy@moltenimage.com wrote in
>> news:1156033205.645620.308870@b28g2000cwb.googlegr oups.com:
>>
>>
>>>Okay, quick update... new fuel pump in, took care of the voltage drop
>>>problem... now we're getting an ALMOST-start. It cranks, it tries to
>>>catch, it won't quite take off.
>>>
>>>ECU gives a code 16 ("Fuel Injector System: defective circuit or
>>>unplugged / defective fuel injector".)
>>
>>
>>
>>
>> Wanna take a second look at that Main Relay?
>
> Already did. All working fine. Came out of another working Civic, in
> fact.
>
> Like I said, the injectors ARE working, they ARE spraying fuel (at
> least, the main injector is).
>


So you've for sure got spark, for sure the igniton timing is correct, and
for sure the ECU is driving the injectors correctly now?

Does the car start with a shot of ether?

A code 16 sometimes does actually mean a defective injector.



--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

TeGGeR® wrote:
> Matt Ion <soundy@moltenimage.com> wrote in
> news:mJaGg.440318$IK3.223342@pd7tw1no:
>
>
>>TeGGeR® wrote:
>>
>>>soundy@moltenimage.com wrote in
>>>news:1156033205.645620.308870@b28g2000cwb.googl egroups.com:
>>>
>>>
>>>
>>>>Okay, quick update... new fuel pump in, took care of the voltage drop
>>>>problem... now we're getting an ALMOST-start. It cranks, it tries to
>>>>catch, it won't quite take off.
>>>>
>>>>ECU gives a code 16 ("Fuel Injector System: defective circuit or
>>>>unplugged / defective fuel injector".)
>>>
>>>
>>>
>>>
>>>Wanna take a second look at that Main Relay?
>>
>>Already did. All working fine. Came out of another working Civic, in
>>fact.
>>
>>Like I said, the injectors ARE working, they ARE spraying fuel (at
>>least, the main injector is).
>>
>
>
>
> So you've for sure got spark, for sure the igniton timing is correct, and
> for sure the ECU is driving the injectors correctly now?

Heheheh, funny story...

> Does the car start with a shot of ether?

Wanted to try that, but buddy didn't have any in the shop, and at that point we
didn't have time to go pick some up.

> A code 16 sometimes does actually mean a defective injector.

That's what I figured, but they seemed to bench-test fine.

Anyway... buddy just called, he got it going: new plugs and a fresh battery and
it fired right up. Apparently the Bosch Platinums that came in the thing were
bunk, despite showing good soild spark when tested outside the engine(???).

Would be interesting to see if the ECU is still giving an error code. I'm
wondering if it might have been stored from when the bad fuel pump was still in;
I can see how the pump dragging down the voltage could affect injector
operation, since all three are on the same circuit off the main relay, and the
ECU might read the lack of input signal from the injectors as a "bad" unit(s).
Or it may have even stored that code from when we tested the injector wiring
with them disconnected? How long does the ECU hold codes?

So, another mystery solved... once again, I thank you all for your assistance,
especially the masterful TeGGeR