LS Turbo300

I have a 92 Integra gsr all stock. I went into the doctors today came back out after driving to school all day an the car running fine all day and the car wouldnt start randomly. I noticed the main relay wasnt clicking and the CEL was solid so i got a paper clip an checked the code an the CEL just stayed lit up solid with the key in the acc/start position. I went an replaced the relay with a another new one (i replaced it 3 months ago because it went bad so I used the Warranty) this time it didnt work still got a solid CEL with connector jumped and the fuel pump an main relay not working, What could cause the main relay not to click knowing its new?? Bad Ecu? I dont see the ecu being the problem as it was working fine 30mins before but i know a solid ecu is a sign of a bad ecu.. As of right now my cars sitting at the Docs so any help asap would be awesome!!!

Thanks

slowDB7

Try reseting the ecu and see if it will clear it

fcm

There are three (3) powers going to the PGM-FI Main Relay, a ground, [black], two (2) outputs, fuel injector relay and fuel pump relay] and one switched ground input, [ECU/ECM fuel pump control].

Start by unplugging the PGM-FI Main Relay and testing for the 3 powers, one will be hot at all times, one will be hot when ign. switch is in the run AND start positions and the third will be hot only when cranking to start.

If all the above are good, test the black ground for continuity to chassis ground.

If good you will need to plug it back in and do the "feel" test, hold the relay in your hand and turn the ign. switch on to the run position, [not all the way to start] the relay should "click" two (2) times, the clicks are very close together so it is easier to feel the clicks then hear them.

If there is no click at all from the relay, the switched power, [hot in run and start] is not working or the ground is bad, or the relay itself.

Let me know what you find. 94

LS Turbo300

Hey whats up fmc you always give great info from the posts ive read from you in the past years sense i started the honda game. Well today i didnt have much time as i didnt get the car towed home till late but i managed to find some new problems. I checked all the fuse under dash and hood all was good i tried resetting the ecu like rawrxdino8 mentioned doing above no luck. So i decided to check for spark at the plug wires well come to find out im not getting spark. So im gonna recap all my symptoms im having to be clear: Solid check engine light when ignition is On with or without the cel connector jumped which from what ive her is code 0(bad ECU), new never used main relay not clicking, fuel pump not priming and no spark. All fuses are good starter is engaging just sound like im not get fuel when turning over the engine and now obviously no spark..

So my question and assumption is leading towards a bad/fried ECU. So to figure out if its bad, what ecu's can I hook up to see if I can get the car to fire up? Will a stock obd1 ls ecu work(friends) or a chipped p28 ecu(friends also) work just to see if she will fire up so i know if the is is gone or not??? does it really mater as long as its obd1 just to see if it will fire up i dont want to mess the motor up I just spent $3500 rebuilding the motor an trans and cant afford to mess anything up.

Thanks im willing to try any suggestion given just let me here them!!!!

Crx_owner_20

Try the stock LS ecu. You dont have to start it to here the fuel pump prime. And even starting it to see if it runs wont hurt anything. Just dont drive it so it wont go lean..

fcm

If the PGM-FI Main Relay is not working, [fuel injector relay] the ECU/ECM will not get a 12V+ signal to IGP1 and IGP2 so not only will the fuel pump not work, [ECU/ECM fuel pump relay control] there will be no signal from ECU/ECM to the distributor, [ICM] so no spark.
Solve the PGM-FI Main Relay problem first and it may solve your other problems.

BTW, how exactly dod you "check" the fuses? 94

LS Turbo300

Ahhh makes sense ill go see what i can find out about the main relay and see if i can diagnose it right now. I checked the fuses by just pulling them all out one by one and making sure they wasnt burnt on the ends and wasnt blew out in the middle. Is the any fuse or fuses inpaticullar i should pay more attention too???

Thanks going to work on it now

LS Turbo300

also another question what do i check the continuity with??? Will a test light work? Or do i need like an voltmeter or multimeter?? Cuase i really cant afford to go out buy one of those but i do have at test light.. Do they Have places where ytou can borrow them?

fcm

The 3 fuses for the PGM-FI Main Relay are...

12V constant, fuse 38 -10A in engine bay fuse box, yellow/white lead at relay.
12V switched, fuse 24 - 15A in under dash fuse box, black/yellow lead at relay.
12V switched/start fuse 18 - 7.5A in under dash fuse box, blue/white lead at relay.

Eyeballing a fuse is not a good way to test a fuse, hairline cracks are very hard to see, even when using a magnifying glass, best way is to test them in the fuse box using a cheap 12V test light, [not the LED type], touch test light probe to both test tips on the fuse. 94

LS Turbo300

Ok i just went out there and did your test and another test i found searching the web. I unplugged the main relay used at test light im getting power to all three terminals. So i did the jump test by connecting a strip of wire from terminal 7(Fuel Pump) to terminal 1(hot at all times and got power to the fuel pump and then i did the same for terminal 3(ECU/im guessing its for the fuel injectors YEL/BLK wire) to terminal 1(hot at all time) and got had nothing at he fuel injectors they made no noise or nothing but i really didnt know what i was looking for. So what do i have to do to get 3-1 to work???

Im also getting power to all 3 fuses you mentioned above. i checked them with my test light all was good.

LS Turbo300

Alright I just want to let everyone know that i just got done testing the new main relay by hooking it the battery with some electrical wire with the ends striped off following my helms. I first hooked it to the pos. to #4 an neg. to #8 terminal and the main relay clicked so the i moved on to hooking the pos. to #5 an neg. to #2 terminal and got a click so i moved on to hooking the pos. to #3 and neg. to #8 and got the final third click the relay does so i know i didnt get a faulty relay so it has to be in the wiring. But i dont see what except what ever is stopping the injector from working when I jump the main relay connector from 3 to 1 as stated above???? Also will the CEL not cut off when the key is in the run position II unless the main relay is working because i think thats the reason it stays on with or without the service connector jumped???

Thanks fcm for all your help I really dont think i could of got this far without you pointing me in the right direction.

LS Turbo300

bump

fcm

If you have all three powers at the relay plug, the PGM-FI Main Relay will click at least one time when you turn on the ign. if it does not, there is no ground, #2.

Plug the relay in and see/hear if you get the one click.

If you do, then with the relay plugged in and ign. on, use a jumper to supply a ground to #8, ECU/ECM fuel pump relay control lead.

If the fuel pump starts running, the PGM-FI Main Relay is good.

The test you did to power up the fuel injectors will get you no sound whatsoever from the injectors.

If when you plug the PGM-FI Main Relay in and turn on the ign. and get the one click, thest for power at the injectors, wire that is the same color at all four injector plugs should have 12V+ on them.

Let me know what you find. 94

LS Turbo300

just need a response fast so i can continue problem solving in this 35 degree weather lol even tho its dark. Im determined.

Ok so basically your saying if i get one click when i turn on the ignition i then can use a piece of wire an ground it myself to a good ground spot and run it to #8 on relay plug with relay plugged in???

Also I have already checked the ground on #2 terminal to thermostat housing and its tight. Can I just make a ground close to the relay and run it to #2 terminal and see if i get a click from the relay?? Or does it have to be grounded to the thermostat housing???

LS Turbo300

Ok when i turned the ignition on the relay is clicking once for the injectors so i jumped a ground from the chassis to the #8 and the fuel pump cut on so the relay is good but unless i supply my own ground, the relay will not do the second click like it should. What is stopping the relay from doing that second click to the ECU/ECM fuel pump relay control lead???? Im going to test to make sure im getting power to the injectors now.

Plz help is needed here im starting to run low on ideas of what to test next thanks

fcm

It is the ECU/ECM that supplies that ground to #8, [fuel pump relays coil].

Besides the fuel injectors, fuel pump relay coil, [internal] a few engine sensor/solenoids, the fuel injector relay also supplies the ECU/ECM with 12V+ to IGP 1 and IGP2, if either IGP1 or 2 does not get power the ECU/ECM will not supply the ground to the fuel pump relays coil, #8.

Pull the ECU/ECM and test for power at IGP1 and IGP2, [ign. switch on] the leads will be the same color as the power leads at the injectors and will be the only two leads of that color at the ECU/ECM.

If there is power at IGP1 and IGP2 it is a good bet the ECU/ECM is the problem. 94

LS Turbo300

Alright i just test for power at IGP1 and IGP2 and they both are getting power same for injectors. So my guess is that the green and black wire/#8 terminal on relay connector is the ground supply from to ecu to the fuel pump right?? and the ecu is not supplying it so the ecu could be the problem right??

And also a question if the ecu is in fact the issue and i need a new one and sense the ecu for my car is soo rare and expense could i just get an obd1 ecu from a b16 or a P72 and just get a chip from some where like xecronon and run b17a1 basemaps on that ecu so basically it would be a b17 ecu just using P72 or b16 ecu hardware??(car is completely stock if it matters)

fcm

The ECU/ECM supplies a ground to the fuel pump relays coil, not the fuel pump, but yes it is the #8 terminal on the PGM-FI Main Relay and if it is a green/black lead then find that green/black lead, [A7/8].

try the same test as above but this time supply the ground to the green/black at the ECU/ECM, if pump still turns on, it confirms the ECU/ECM is the problem and not a connection problem between the ECU/ECM and the PGM-FI Main Relay. 94

anon99

Did you ever solve your problem?