1990 honda civic

can someone tell where the fuel pump is on a 4 door 1990 honda civic. i am
having a problem with no gas getting to the injecters what can be the
problem. someone told me there was a relay under the dash that controls the
fuel pump is this true?

 

If you don't get any responses except for this one, I suggest that you
visit several auto parts stores in your town and buy a repair manual for
your car. I have a manual made by a company named Haynes and the manual
has really helped me find various parts on my car. Manuals by some of the
other companies are even better. The Haynes manual for your car should
have the following code number:
42023--Civics all models 1984-1991

 

that's great for most things, but in this instance, none i've seen
adequately address the main relay issue. that's the single most common
failure on this vehicle, and likely exactly the problem experienced by
the op.

 

The main relay is indeed the prime suspect for that - see
http://tegger.com/hondafaq/faq.html#MainRelay

The relay can be replaced or resoldered (the solder connections on the
internal circuit board crack).

Mike

 

Here's something else to consider when making the repair/replace decision...

When I took my dead main relay apart I found that the relay contacts were
burned and pitted like an old set of ignition points. Resoldering the relay
would not have been sufficient to fix it. However, I probably could've
polished the contacts with some 400 grit sandpaper but I decided to replace
it with a new one since the original one lasted roughly 180,000 miles and I
suspect that the new replacement will last for the remaining life of the
car.

Eric

 

Good point, Eric. Since the relay is no fun to get to, replacement of
something that old looks attractive.

I've worked in electronics for 30 years and my experience is that contacts
that are visibly pitted are hopeless. Relay contacts are plated with
palladium, and when that is gone the base metal under them oxidizes at the
point of contact and ensures intermittents forevermore.

Mike

 

---------------

Best fix . . . replace the relay with a new one, but 'beef up' the
solder on the new one, since wave solder on Japanese items can be way
too thin to support the weight of a relay flopping around for 300,000 Km.

'Curly'

 

Oops, sent a reply to main poster, not the group.

I have an 88 Civic, with the main relay checking out OK, on continuity, but
low (1-2 volts) voltage getting through to the fuel pump.

Can these relays pass low or no voltage, even though they pass the
continuity tests listed in the Haynes manual?

HELP!!

Frank

PS: Also having other weirdness happening when I press the horn, (key in
off position) the lights that come on at startup light up, and no horn
sounds. Once key is on, this doesn't happen.