KYSI

A friend has a d16 that as soon as you turn the ignition the injectors run constantly. What would cause this to happen? Here is a list of the things they have replaced as a trial and error test:

ECU
Main relay
injectors
fuel pump

I know this is not alot of information, but maybe one of you fine folks have had this to happen to you and may know right off hand. Thanks for the help.

97twodoor

Make sure the injectors are not getting a constant ground source (wire insulation rubbed through the body some where).

newtron63h

either the ecu is getting a bad signal and telling the injectors to fire all the time OR like 97twodoor said there is a short to ground. just to make sure, its ALL the injectors? thats a bit of a weird thing if all the in jectors have a short to ground. easy way to est the short. unplug the connector at the injector, check for continuity from theground terminal to a known good ground, do this with key off engine off. if you DONT have continuity then you know the harness is good. so from that point it is figuring out where the bad signal thats telling the ecu to fire the injectors is coming from. id start with the cam/crank sensor.

KYSI

Thanks for the advise. They found the wiring harness destroyed under the dash. Once they replace that i will update again.Thanks.

green99civic

The injectors use a transistor for each on inside the pcm which switch the injectors on and off. The car as soon as you turn it on there is 5 volts at the injector that goes through a coil which triggers a magnetic field that opens the injector, obviously there is getting voltage there, which means the sensing wire back to the pcm is getting shorted some how or it could simply be the ground after the transistor or the transistor in the pcm could be bad.

KYSI

All wiring harnesses were replaced from dash to engine bay. The complete manifold assy and all grounds have been swapped and the injectors are still spraying non-stop. This is beyond me so I think its time for a professional.

hbhero

Any solution yet? I just bought a 98 Integra GS that's doing the same thing. It basically hydrolocked the engine with fuel. It kept pumping to the point where gas was coming out of the intake. Here is my troubleshooting progression:

1) I checked the fuel pressure regulator to see if the diaphram went bad and was pumping gas into the engine. It isn't.

2) I pulled the injectors, metered, checked, and cleaned them. All worked properly and held back 45psi of air.

3) I changed the oil (mostly gas now) and tried starting the car. No luck.

4) I've checked the main relay. It seems as though the ECU isn't turning off the ground to stop the fuel pump after two seconds. I thought that might be causing too high of fuel pressure for the injectors but isn't that what a return line and fuel pressure regulator are for??

5) I checked all distributor sensors thinking they might be giving a bad signal to the ECU. All were ~350 Ohms, no direct shorts.

6) I noticed when plugging the injectors in they click on. For some reason they are constantly on. In fact, one of my cylinders was on the intake stroke and with the sparkplug out I can hear the injector spraying when I plug it in. Here is the source of my flooding problem.

7) I unplugged the ECU and checked for a direct short to ground on the injector colored wires (not yel/blk which have power btw). No short. With the ECU plugged in (ignition off), the grounding wires (colored ones) show about 1.9MOhms. Seems fair if it is a transistor that grounds it.

Next step: buy a new ECU unless someone suggests something else to check. With the ground not being removed to shut off the fuel pump and the injectors stuck on it would be my next guess. If anyone can point me to some more info it would be greatly appreciated. I've found a few people who've posted with this problem but no solution.

hbhero

UPDATE:
I noticed a low humming sound with the key turned off. I unplugged the main relay and it stoped. I pluged the relay back in, turned the key on and back off, and noticed the sound again. By backprobing the relay I found the fuel pump was getting ~3V with the key turned off. I checked the ignition wire and found the same. I probed the connector w/o the relay plugged in and there is no voltage (as it should be). I am beginning to think something is wrong with the relay. I took it apart, tested the three diodes and power resistor and everything looks normal. There are two separate relays inside (one 12V and one 4V) I haven't tested because I am not sure how they are configured. I just snagged one so I'll keep my fingers crossed.

hbhero

UPDATE:
I got the main relay in and tried it out. It stopped the voltage going to the fuel pump after the key was turned off but didn't stop the injectors from coming open or the fuel pump from staying on. I checked over everything again and I seem to be coming back to the ECU. The CEL turns off after 2 sec. once the key is turned to 'ON' but the fuel pump keeps pumping and the injectors keep dumping. A new used ECU is on the way.

civic_driver

I'm thinking the problem is around the main relay somewhere. Either the main relay, the wires around it, or the main relay holder/connector.

If not that, then the ECU is most likely to blame.

maguswagon

Is your car DPFI or MPFI? If it's DPFI then you may want to check out this PDF.

http://hondainfo.hottamale.hu/manual...ch/chpt_21.pdf (you may have to right click, save link as)

Basically it says that the lower injector o-rings leak causing unmetered fuel to enter the engine. Apparently there's a TSB and a 'purge kit' from honda (part# 04103-SH3-K30). I'm having basically the same issues and I just ordered the o-rings from Honda. The o-rings were around $20 and should be here Tuesday.

rick_rabies

my precisions 1000s did this. 1 of them i forgot to put in the resistor box. fried the injector jumpers in the ecu. put in resister box, new chiped p28, straw in teh cylinder and SUCKED THE GAS out of the engine(not recommend) fired right up

hbhero

Both the OP and myself replaced the main relays and it didn't fix the problem. I also metered the **** out of mine and can't find anything wrong with it.

AFAIK D16s were never DPFI and of course my '98 is not.

The thing is, this car was a kids daily. I can understand missing a wire but this thing ran for over 120k. It just up and died one day and ended up in my hands.

I am awaiting a new ECU, fingers crossed.

maguswagon

Just to give an update on my situation. The injector o-rings themselves didn't fix the problem. However, I ordered the purge kit that I mentioned above and it solved it. My car was running way rich and failing miserably on hydrocarbons and CO. After the kit it passed with flying colors.

Oh and just so you know the kit comes with both injectors and the purge line that goes from the canister to the intake manifold. It was $190 from the dealer which is less than half the cost of the individual parts. I did notice the hose had a metal restrictor inside it whereas the original did not. I think the problem with my car was sticking injector(s) though.

hbhero

UPDATE:

I got the ECU and everything acted the same as before except for two things I noticed.

1) The speedo and lighting were for a short period of time erratic w/ the new ECU.

2) I was able to pull codes P1298 (ELD High) and P1660 (A/T something)

Because of code P1298 and the erratic electrical system I figured I'd check the ELD. Instead of 4.5-5V from the ECU on the green wire, there was ~8.6V!!! WTH!! I'm stuck. I am just guessing blindly now.

HELP PLEASE!!

I know there was a pretty beefy stereo in the car wired directly to the battery. Could that have fried the alternator causing some surge to the ECU and frying it? I think I'm going to buy another ECU and disconnect the alternator before trying to start the car. Like I said, I'm just blindly guessing. In fact, I'll paypal $20 to anyone that can give me the solution.

civic_driver

The car won't run without the alternator attached. You need to fix this ELD problem which is probably causing your problems and might have fried your ECU.

hbhero

Does that have something to do with the car being OBD2? If the alternator were to go bad would the car not run at all?

I think for $20 I am going to buy a new ELD and give it a shot. Does anyone have any info on metering the ELD pins? Not the 12V, 5v, and ground but the ELD itself. Any resistance specs on it?

civic_driver

I don't think you can run a car with just the battery, without the alternator. And it doesn't have to do with the car being OBD1 or OBD2. It's just the way the electronics are made to work. You can try to verify.

hbhero

Yea, you can definitely run a car w/o an alternator, your battery will just go dead eventually. The battery and alternator work in parallel and if either one fails the system as a whole still works.

patolscivic

my buddies got an integra with the exact same problem has anyone figured this out yet?

Oranged3mon

Any one get this figured out?