i wasnt gettin any power to teh pump so i was checkin teh main relay wit a test light and when i got to the one wit the red circle the light went on and teh fuel pump turned on…when i removed the test light the fuel pump went off…any ideas??
The green/black wire is the fuel pump relays control wire from the ECM, the ECM supplies the relay coil with a ground, [you did that with the test light] the 12V+ for the relay coil is supplied from 2 places the primary is the yellow/white wire, fuse 38 - 10A, [hot at all times] in under hood fuse box it is the input power for the injector relay, one of two relays in the “PGM-FI Main Relay”, injector relay coil is controlled by and the fuel pump relays 12V+ input is the black/yellow wire, [which is weird because I do not see a black/yellow wire in your pix] it is fused at fuse 24 - 15A, [hot in run or start] in under dash fuse box, power for fuel pump relay coil is internal.
There is also a secondary power for the fuel pump relay coil, blue/white.
1- Black… ground for injector relay, [ground at all times].
2- Black/yellow… control for injector relay and 12V+ input for fuel pump relay, hot in run or start.
3- Yellow/black… 12V+ output from injector relay to ECM and injectors, [hot in run or start if relay is working]
4- Yellow/white… 12V+ input for injector relay, [hot at all times]
5- Blue/white secondary 12V+ for fuel pump relay coil, [hot in start]
6- Green/black… 12V-, [ground] control to fuel pump relay coil from ECM, [ground when ECM turns it on]
7- Yellow/black… 12V+ output from fuel pump relay to fuel pump, [hot if relay is working and/or if ECM is sending "PGM-FI Main Relay, (fuel pump relay coil) the ground it needs].
Hope this helps, however it sounds like ECM is not sending the ground signal to the fuel pump relay coil to energize it.:think: 94
the fuel pump will work sometimes but the main relay will click all crazy
Because there are 2 relays in the “PGM-FI Main Relay” it is hard to tell what is wrong as both the fuel injector relay and the fuel pump relay will effect the fuel pump, however, what you should hear/feel when you turn on the ign. to run, [not start] is 2 “clicks”, [may sound/feel like one as they are very close together] first the injector relay energizes, [closes] then the fuel pump relay energizes then 1-3 sec. later the fuel pump relay “clicks” off, [once fuel lines are primed] at the same time as relays first come on you will hear the fuel pump also come on, [priming] when you head/feel the fuel pump relay “click” off, [in a few sec.] the pump will also turn off, when you crank to start the fuel pump relay will energize, [“click” closed] again and fuel pump will turn on again, it should stay on from then on.
If it “clicks” on and off constantly when ign. is on, [motor not running] it can be the relay or the ECU, to test use a multimeter on the green/black line, [fuel pump relay control line from ECU] it supplies a ground to the relay coil, to energize it, it should come on, [show a ground] for a few sec. then turn off, if the output from the ECU keeps tuning on and off so relay “will click all crazy” the ECU has gone west.
Will the car start?
If the car will not start try this, unplug the “PGM-FI Main Relay”, depin the green/black wire, reinstall the the relay with a jumper lead ground the terminal that the green/black wire was in, [fuel pump should turn on] and try and start car, if the car starts, again test the output of the green/black wire, it should show a constant ground.
If car will not start or runs intermittently, [“PGM-FI Main Relay” “clicks like crazy” I would meter the black/yellow, [should show 12V+ constantly once ign. is turned on and when starting the motor, check the check the yellow/white, it should show 12V+ all the time, [ign. off/on and when starting] and check the blue/white it should show 12V+ only when cranking to start the car.
Test the above and let me know.:idea:94
it was a bad connectin at the ground at teh thermostat
did u figure out wat ur lookin for??
i have the same problem… so wat did u do with yours?
Geez wham. I think someone would help you in the first thread you replied to. I have read your ‘i have the same problem’ in 2 threads now plus you created a own thread.
[QUOTE=fcm;1525444]…I would meter the black/yellow, [should show 12V+ constantly once ign. is turned on and when starting the motor, check the check the yellow/white, it should show 12V+ all the time, [ign. off/on and when starting] and check the blue/white it should show 12V+ only when cranking to start the car.
Test the above and let me know.:idea:94[/QUOTE]
so what does it mean if you test the first two and you get the 12V+, but when you get to the blue/white one, you only get 9V+ when you crank to start?
[QUOTE=slowassciv33;1524401]
i wasnt gettin any power to teh pump so i was checkin teh main relay wit a test light and when i got to the one wit the red circle the light went on and teh fuel pump turned on…when i removed the test light the fuel pump went off…any ideas??[/QUOTE]
main relays do take a crap mine and a friends did within a week apart. u can get them at a junkyard for like $5 an $10. i just call acura and got 1 for $47 new pump works great now.
so what does it mean if you test the first two and you get the 12V+, but when you get to the blue/white one, you only get 9V+ when you crank to start?
It means the batt. is a little low/weak, a drop in voltage on any line when cranking to start is not unusual.:think:
What problem are you having?:hmm:
main relays do take a crap mine and a friends did within a week apart. u can get them at a junkyard for like $5 an $10. i just call acura and got 1 for $47 new pump works great now.
They are also easily repairable, most of the time, the most common problem is cold solder connections on the circuit board. :whisper: 94
[QUOTE=fcm;1736232]It means the batt. is a little low/weak, a drop in voltage on any line when cranking to start is not unusual.:think:
What problem are you having?:hmm:[/QUOTE]
car cranks and turns, but doesn’t start… I’m still semi-n00b status and I’ve been testing everything using the haynes manual… the battery is fine, the distributor, rotor, wires, plugs and fuel filer were all changed in May, the coil output is within spec, the ignition module tested fine… just last night I was testing for voltage and continuity with the various connections for the MFR and that seemed fine… I can’t remember if the relay clicks when trying to start the car, but it would definitely click when I would hook up the battery to test it… so now I’m trying to figure out how to test the ECU and move my way to the fuel pump which does not prime when you go to turn the engine on… also when trying to push start/pop the clutch, the car sounds like it’s trying to run but then sputters out…
I haven’t been posting anything because I’ve been trying to avoid getting flamed for not searching, but it’s hard to get one cohesive solution… since this was on-topic and was something that I have noticed, I figured I could ask without getting shot at… as far as the voltage thing I was told that because that wire in particular goes to a diode, it would be acceptible for the voltage to be slightly lower, but that wasn’t from a car person…
The guy that wasn’t a car person, is correct, there is a diode in the line, I am not exactly sure what the role of that lead is, but it has none when ign. is turned on, and would have no effect on the priming sequence.
When you turn on the ign. the injector relay turns on, it supplies power to the injectors, some sensors, the ECU/ECM, and triggers the fuel pump relay, [one side of relay coil] the ground for the relay coil is supplied by the ECU/ECM, the fuel pump relay will stay on for a few short sec. then “click” off, [ECU/ECM cuts ground to fuel pump relays coil.
The other thing that is happening, when you turn the ign. on is, you can hear the fuel pump turn on and prime and then turn off.
If you hold the PGM-FI Main Relay in your hand and turn on the cars ign. to run, [NOT start] you will feel, and hear] the double click of the injector relay and the fuel pump relay turning on, it’s almost one “click”, [may even feel/hear like one to you] at the same time the CEL light in the cluster comes on and you can hear the fuel pump hum as it primes the fuel lines, in a couple of seconds you will feel/hear the fuel pump relay “click” off, the CEL light in cluster goes out and the hum of the fuel pump stops.
All the above is normal and should happen exactly as described, if not, you have a problem with the PGM-FI Main Relay, it’s wiring, the ECU or the fuel pump.
Need year of car to be of any more help.94
it’s a 90 LS…
now if the wiring that plugs into the relay which I tested for voltage is ok, would the next step be testing the ECU? I’ve been saving testing the actual fuel pump itself for last because I really don’t want to have to take out the back seat if I don’t have to…
last time i called about a relay from acura (and bought one) it cost me $89, and the piece of shit only last 3 and a half weeks or so. im amazed you got one so cheap from the dealer
the one i got heated up and burned itself out, and they wouldnt replace it. went and got a junkyard one for a few bucks ($10 at most) and was still working when i sold the car 4 months later :shrug:
it’s a 90 LS…
now if the wiring that plugs into the relay which I tested for voltage is ok, would the next step be testing the ECU? I’ve been saving testing the actual fuel pump itself for last because I really don’t want to have to take out the back seat if I don’t have to…
A lot of testing, including fuel pump, can be done right at the PGM-FI Main Relay plug.
If you do not hear the fuel pump come on to prime the fuel lines when you turn on the ign., confirm that there is 12V+ on the black/yellow lead going to the relay when ign. is on.
If so, test for 12V+ on the two yellow/black leads, one of them, [injector power] should stay live as long as ign. is on, the other, [fuel pump power] will be live for a few sec. then turn off.
If the above is not happening, use a jumper lead and jump from black/yellow to the yellow/black, [one at a time], the fuel pump will come on when you jump from the black/yellow, [12V+ when ign. is on] to the fuel pumps power lead, one of the yellow/black leads, if the pump does not come on you may have a problem with the pump.
BTW, on a G2 you have to drop the gas tank to access the fuel pump.
You say you have tested for power at the plug, and it’s “OK”, what does that mean exactly, power is OK on what leads when?
On my previous post I explained what you should feel and hear when you turn on the ign. to run, [not start], have you tried that?:tapfing: 94
[QUOTE=fcm;1736587]
You say you have tested for power at the plug, and it’s “OK”, what does that mean exactly, power is OK on what leads when?
On my previous post I explained what you should feel and hear when you turn on the ign. to run, [not start], have you tried that?:tapfing: 94[/QUOTE]
I checked for those sounds again, while I did not hear them before testing the the relay the other day, I DO hear them now, so I tried starting the car a few times and on the third try it actually started up but was running EXTREMELY rough and shaking a lot while backfiring a little bit…
when the fuel pump came on it did not sound as smooth as I think it usually does…
as far as testing the relay connector, I got voltage at Terminal 1 & ground, Terminal 5 with the key going on and off, and then Terminal 4 & ground when the key was in the start position…
Terminal numbers do not help, wire color and tracer do.
Have you tried to “jump” from the 12V+, [when ign. on] to the fuel pump power lead. [yellow/black]?:hmm: 94
[QUOTE=fcm;1736643]Terminal numbers do not help, wire color and tracer do.
Have you tried to “jump” from the 12V+, [when ign. on] to the fuel pump power lead. [yellow/black]?:hmm: 94[/QUOTE]
yes, just did it… when going from blk/yellow to yellow/blk it clicked and when going from blk/yellow to yellow/blk w/ red dots it sounded like fuel was flowing…
Does the car run?:hmm:94
well like I said earlier this morning, I tried starting the car three times once I heard the relay click and the fuel pump prime, on the third time it actually started up but was running EXTREMELY rough and shaking a lot while backfiring a little bit…
when the fuel pump came on it did not sound as smooth as I think it usually does…