98 Honda Civic Dx, Stock D16Y7

Car was converted from an auto to manual.

Finished the swap sunday morning, car ran great monday and monday night put about 40k on it..
Tuesday I go out to start it and its running on 3 cylinders... I did the obvious at 130k,

Replaced plugs. Still missing here and there but alot better than before. I head to school.
On my way home I stopped and got a set of wires. Put them on.

STILL missing, but its doing waaaay better, prolly a cap and rotor next (i think).

Came out this morning, back to 3 cylinders. Dead miss.

I'm getting fire/spark from all four cylinders, so I check my injectors. #1 cylinder. No fire on injector. so I switch injectors with some others I have on the shelf. Same problem. I can unplug the injector as the car is runnning and it makes no difference.

So I googled this problem, came up with either a bad wire (which i highly doubt bc everyone that said that had a bad wire. it was cut or slit during a swap and there car ran like poo right off the bat.) Car ran PERFECT for the 1st day and I did nothing to it but run errands. The other option was a bad ECM/ECU.. and Well im kinda stumped and I dont want to keep buying random parts bc Im a student and my old man doesn't like to be the national bank to keep loaning me money till payday.

Please any info??

 

Harness probably rubbed through under the intake manifold, '96 - '99 Civics (2000 models are supposed to be unaffected) were notorious for having the wiring harness rub through on the IM stiffener bracket and short out causing all kinds of funky issues, its possible it got distrurbed when you did the swap and its now shorting out.

 

Not what I wanna do in the dead of winter ugh, Alright Ill head out now and start looking. Should I unravel the harness? or do you think I should be able to see clearly where the wire got rubbed?

 

Theres 2 dead end plugs under the IM, one gray, one blue. It'll be in the last few inches of wire going to one of those 2 plugs.

 

Does the #1 injector clip have battery voltage with the key in ON(II)?

 

well its freezing out!! But I did check the harness, and its pulled away from the IM. There is no indications of any rubbing or friction whatsoever on the loom. Should I just take a knife and cut the whole harness open and just trace wires?

Good call on the grey and blue plug, Right on the money!

 

^ do this before you start taking apart the harness

 

Can't find my test light, I have a volt meter... but um well I dont know how to use one.

 

flip it to vdc, place the black probe to a ground source and the red probe to the yellow/black pin on the injector plug

 

The injector clip has two wires, a power wire from the main relay and a ground wire that runs to the ECU. You could potentially save yourself a lot of frustration by testing the power wire for voltage and the ground wire for continuity using a multimeter.

 

Alright, got the same volts, from injector 1 as injector 2, So is that safe to say its not in my harness? I have already switched out injectors once. Should I try a second.



EDIT: Also I just put injector 1 clip on the injector 2 and started it up. Injector was firing, So I dont think it's in the harness.

 

you have a faulty injector.

 

You guys are gonna love this... All i can do is laugh. Well when I put the plugs in (it was cold obviously and I was late to school) So i DROPPED them in the tubes....

(go ahead and say it ya dumba$$)

Well that took the gap from .44 to basicly touching the diode , no gap whatsoever on cylinder 1. Explans the misfire huh

Thanks for all your help, I'm going to check ALL the plugs now, but I re-gapped that one and its running like a champ again!

Thanks guys

 

Lol, glad you found the probem, easy fix

 

This is possibly the only time when one of those cheap engine dress-up plastic tubes improves the form and function of your car.

 

having a very similar problem on my 89 crx, but can't figure it out. read slowls-eg's post on how he fixed it and can't really figure out any of the lingo used. I'm new to fuel injected engines (ive worked on carburetters my whole life) so i'm not really sure what the "gap" is. would someone care to explain? it would be greatly appreciated.

 

Spark plug gap, he dropped one of the plugs and didn't notice that the negative electrode bent and was touching the positive electrode, actually doesn't specifically have anything to do with fuel injection.

 

thanks for the quick reply! well unfortunately i'm only getting power to one injector so i will check my spark plugs but i don't think it would be them because it starts with starting fluid so assumed its getting spark to each cylinder.

 

if you have a dead cylinder try doing a compression test on all 4 cylinders see if you see a difference in the readings also when checking out the spark plugs look at them closely and it will tell u how the motor is running too black means rich too lean itll look cooked and flakey on the tang and electrode the plug should look like if u dipped it in coffee a light tan on the white part see if this helps any of u I used too work at a machine shop and on V-8 and first thing we check before tearing the heads apart is too examine the heads and plugs youll see if a cylinder is running FAT or lean.....

 

Post your problem in the EF subforum (88-91 Civics). The injectors get power via the main relay. Sounds like you have a broken wire somewhere between the main relay and the injector.

 

posted https://honda-tech.com/forums/showth...5#post44256795 thanks

 

i have this same dman problem on my dc2.ive changed plugs, leads dizzy, had timing checked..did a compression test even numbers all around.

but my problem is intermittent. sometimes the car runs totally sweet..then sometimes..at idle....it will just start missing on cylinder 1.when i pull out the injector clip it makes no difference so im assuming its a faulty ecu or bad power wire from the main relay?

can some 1 just confirm that it will not be my engine as if my engine compnonets were messed up they wouldnt be sweet sometimes then not sweet other times!?

i have a small water leak on 1 of the pipes near the fuel filter but i really dont think that has anyhting to do with the pulses going to the injector.

i even replaced the injector. all i can say is sometimes..the power to injector 1 stops working and i get like a tappet/LMA noise coming from the head.

other times the car runs sweet with no tappet noises and no misfire.

also my rev limit changes too...sometimes it goes close to 9k...n sometimes it struggles to get past 8k.

can any 1 give me any advice or had similar problems? im reaaly hoping its just a abd wire or fualty ecu...i recently had a new engine put in to...old 1 died of oil starvation i didnt check the oil level (yes stupid me) prior to this all the components were running perfect..i just had the actual engine itself swapped over. i put it on a diagnostic and no codes are showing up....and its blatantly misfiring on cylinder 1 and i dont even get a misfire code! i guess if no fuel at all is going it might not even count it as a misfire lol!