ok 96 accord wont start, i've just changed the fuel pump cause i didnt hear it turn on when i opened the ignition, and the car still wont start. i checked the main relay and it tested fine, and i also checked the fuse. i opened the test port on the fuel rail and theres no pressure coming out.
the car has spark and the the timing belt is fine, there's just no fuel pressure.
any ideas, please help......

 

Have you traced the circuit for continuity? Personally, I wouldn't have replaced the pump until I ruled out broken wiring.

 

When you first turn the key on your check engine lamp should light up and the fuel pump should come on to purge the fuel rail, the check engine light should go out in a few seconds and the fuel pump should die also. The CEL is your tell tale indicator that the main computer is in control. The main computer is also responsible to ground the coil portion of the main relay which magnetically attracts the fuel pump relay switch portion of the two relay portions of the main engine relay combo.

Simply the main relay has two internal relays, one is responsible for the fuel pump, quite often the relay contacts have a cold solder or poor connection on the circuit board, it may test fine when you push on it with your meter probes but it will not make contact otherwise. Try cranking your engine and tapping on the relay with your screwdriver handle while holding the key in the start position, dont be shy, see if the car starts up. This test is not full proof but as mentioned, you need to chase down the voltage loss to the pump otherwise.

Check CEL operation, smack main relay while cranking, do a voltage test around needed areas for the fuel pump circuit, get some more help with all your newly learned diagnostic procedures already carried out and use this info as ammo to track down the culprit, good luck.

Duane in Japan

 

A silly question,, but how did you test the main relay ???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by deserthonda &raquo;</TD></TR><TR><TD CLASS="quote">A silly question,, but how did you test the main relay ??? </TD></TR></TABLE>
Helms manuals have a test where you manually energize the relays with power and ground then check for continuity. IMO it's not a very good test because most main relay problems are intermittent.

 

this might be a silly way to test but, the way i did it was, i installed it on another accord and it cranked up just fine. it might have not been the best way to test it, but it seems to work fine on the other accord.

 

no crank at all??

 

Toy like Chio has stated before those relay act intermittently , you need to take relay casing apart and chk for cracked solders,,

 

Relay was taken apart and resolder...... still nothing

 

ok so now we know relay is good next step it to back at fuel pump and make sure you have power and a good ground .. if you have both and not getting fuel fuel pump is no good

 

sorry hit the wrong key if you are not getting either power or ground you got an issue with wiring,,,, try spraying carb cleaner in throttle body see if that starts the car ...you also said you put a new pump already ws it a honda pump???

 

not a orginal honda pump, but i tested the original one after i took it off and it worked just fine after i changed it. i'll test for power when i get home today....

 

chk under-dash fuse # 9 7.5 amps,and # 2 15 amps , if ok chk power at black/yellow wire at fuel pump plug, and chk ground on black wire ..

if you are not getting any power assuming fuse is ok could be a bad relay or wiring .,,,if you are nor getting groung bad wiring or poor ground source ...if you have both than i have to condemn the fuel pump

 

Sounds like your fuel pump is a bad one, or you hooked it up wrong.