Mike McDonald wrote:
> Thanks,
> Reconnecting the secondary does cause engine to reflood. I checked the
> injector out of car with a nine volt battery and it clicks OK.

that's good, but clicking != guaranteed correct function.

> When in car,
> it does
> not leak when fuel line comes up to pressure, only when engine cranking or
> running,
> which makes me wonder if ECU is telling it to open.

the best check is to get a scope & look at the signal. if it's the same
as a functioning dpfi civic, it's not the ecu, but it's not likely to be
the ecu anyway.

> With other older FI
> systems I've
> worked on, the MAP sensor had the ability to stop the engine from starting
> or running
> by making the mixture go too rich. Would like to be able to verify MAP is OK
> or not
> to isolate problem to the injector. Voltages to the MAP connector OK, but
> there is no
> test given to test the MAP by itself. Don't get a trouble code for the MAP,
> but don't know
> if the ECU would set one or not.

ecu will almost certainly set a code on the map sensor [or ap sensor in
the passenger cabin] being defective.

> No reason to suspect the ECU is bad at
> this time, and they
> are usually the least likely to fail. Was wondering if there seemed to be a
> history of either a
> FI sensors going bad or injectors failing before I resort to replacing
> parts. Will check the
> tandam valve, mostly I'm holding that open manually to see down the barrel.

if you hold the tandem open while you're running the engine, you'e going
to have a problem - it works /with/ the auxillary injector to make sure
there's sufficient vacuum to vaporize the fuel. no restriction from the
tandem = no vacuum = "excess" fuel.

btw, what symptoms make you think it's flooding? if it's simply not
starting, check the main relay. your vintage civic is a prime candidate
for this very common problem.

otherwise, get yourself to a junk yard & get an auxillary injector.
they rarely fail, so a used one is likely to work just fine - at least
good enough to get a decent diagnostic.

> "jim beam" <nospam@example.net> wrote in message
> news:iO2dnZYBP5GMqUbfRVn-qQ@speakeasy.net...
>
>>Mike McDonald wrote:
>>
>>>Anyone know how to troubleshoot a 90 1.5L with dual point fuel injection?
>>>Will only start and run with secondary fuel injector disconnected.
>>>Otherwise floods out and won't run. No trouble codes unless injector is
>>>unplugged. Neither injector seems to leak only spray while engine is
>>>cranking. Tried all the tips in the Haynes book and all voltages and
>>>resistances seem OK for the injectors, MAP, temp sensor, air controller,
>>>etc. Any other ideas? Thanks
>>
>>secondary may be sticking open much longer than required. can you start
>>the engine with secondary disconnected, then reconnect once running? if
>>so, does it run ok or flood again? the secondary should not [or hardly]
>>be injecting at idle, only on enrichment. if you can see it throwing
>>fuel, with the engine warm at any rate, it's sticking open.
>>
>>on a related matter, is the tandem valve opening ok? check it by
>>disconnecting the tube on the diaphragm, opening the tandem valve [that's
>>the "choke"-like thing at the top of the throttle body] and putting a
>>wetted finger over the diaphragm inlet. the tandem valve should stay
>>open. if it closes, the diaphragm's shot. that's uncommon. much more
>>likely is that the vacuum tube from the actuator is leaking. simple &
>>cheap to replace about 1.5".
>>
>
>
>