Sup everyone new to forum and never really had an issue that i couldn't fix, but I've finally met my match it seems so I'm reaching out for help, and wanted to know what does it mean if cel light doesn't turn off after 2sec but fuel pump primes and power supply to injectors and ecu verified,ignition has spark but injectors not pulsating and tachometer not working when it always has so first thought was icm, It's a 93 accord wagon with jdm f23, car has sat longer than it deserved but have 2 gsr's and del sol vtec and wagon doesn't have the available rpm's at times needed for a wide smile 8k+ rpm's give, car did always have its moods where sometimes when interior temps get hot it would only start once cel light went off after air cooled interior changed main relay to no difference but car has never left me stranded whenever it was driven up until know which has been weeks trying to figure out this issue, but never really had any problems with it until recently decided to drive and wont start,unless brake cleaner sprayed into tb and fires up immediately any ideas? Much appreciated for any info on possibilities. Have done most of the obvious things and nothing stands out from normal,has fuel pressure,has strong spark but cel light doesn't go off no matter what temperature interior is day or night im scratching my head and been in the honda game for decades with countless swaps accord,tegs and civics but dont know everything and never to old to learn something new im all ears.

 

The ECM control how the injectors operate (pulsing) by providing ground.

 

 

Is the coil sending power to the ICM?

 

yes car starts up immediately if sprayed brake clearner into throttle body and fuel rail is pressurized but injectors aren't pulsating to inject fuel into motor and tachometer isnt working either and has always worked so whatever is cause of injectors not working is related to tachometer not working which leaves me to either a ground weak,shorted and or wire connection of some sort, but everything i check out of obvious things to check has check out, tryin to figure what wire/wires have in common with injectors and tachometer or can be faulted to cause ecu to not pulsat injectors? Also cel light stays on after fuel pump primes for 2 secs it doesn't go off like it should and that also tells me something other than car isnt gonna start but this is what im lost on is what sign of direction to go in fiding my problem ? And aside from you hasnt been much help with this situation and you know there's had to been someone who has had same or similar problems and what was cause but it isn't really of no help if silence is the outcome 🤔

 

Well was alot of help with injector issue, what about rpm signal to ecu ?? From what i can gather from wiring diagram to ecu there is no rpm signal pin least not with rpm abbreviated so if im correct and if not then explain correctly but ecu would need something to indicate the engine is runing or starting otherwise if it doesn't then power to fuel pump would be disabled for safety reasons correct? And since tachometer isn't moving during starting attempts made then possibly ecu isnt seeing either and fuel pump is only priming the first 2 seconds but not during cranking and so injectors have no fuel to inject (requires constant pressure) in order to get fuel injected ? So my second attempt for help is what pin/wire would this be in regards to cranking/starting or rpm reference to indicate that ?

 

Is there a code?
If the CEL doesn't turn off there is typically a code stored,other wise you may have a shorted reference voltage, faulty ECM or shorted wire....

 

Your tach signal comes from the Ignition Control Mod (ignitor) in the distributor and goes directly to the gauge cluster in the dash. That would be what to look for if the tach isn't working. That has nothing to do with the ECU however. The ECU gets it's engine signals from the cylinder position sensor (CYP), top dead center sensor (TDC) and crankshaft position sensor (CKP) located in the distributor. IF you have an ECU pinout they are labeled as such.

If your check engine light stays solid after fuel pump prime, I would suggest retrieving the codes that are stored on your ECU. They might point you in the right direction as to where to start with your current no start issue.

 

ok thats what im thinkin or possibly the ecu doest see rpm signal and is shutting off fuel pump when attempting to start, but does prime for 2sec and turns off like normal and i hooked noid light to injector plugs and all blink as cranking car so im losing focus on this !!!!! Smh almost lost on what's going on with car. What wire should i be checking? And how do i go about check rpm issue i know its blue wire but will a voltmeter work or do i need some special snap-on tool ? Lmk ive took some time away from car head is beginning to hurt just lookin at it and the results passing from every check i can think of and yet the **** dont start !!!!! And too answer your question no there's no fault codes first think i tried when this began thinking it would just tell me whatever problem is, but that would've been to way too easy of course.

 

Well im pretty sure i said that im aware of blue wire coming from dist as rpm signal wire however if tachometer isnt working is it because of a possible short or damaged wire thats causing this ? Still in works on that answer, but since i said also in last post i believe or before that one that i get solid cel after fuel pump primes, and first thing i did when problem started was check ecu for codes but unfortunately there wasnt any codes given when connector jumped and that if brake cleaner is sprayed into tb it cranks up immediately until burns up brake cleaner and dies, so im in need of some information that i dont know like what/which wire is rpm/cranking/reference input related to ecu/rpm/injector and fuel pump related cause this is a wire/connection issue but which wires and where is what im tryin to figure out but without something to give me sign on what or where to head in finding issue but on this problem its seems to be unfamiliar problem as Haven't had to many responses to this issue aside from efforts made by one or two individuals and thankyou for that much appreciated your time to help.

 

1. The signal from the tach's blue wire is a pulsed signal. A multi-meter set to AC voltage can detect if there is a signal.

2. Remove the ECM and open it up to see if there are any blown or leaking capacitors, or burnt resistors.

 

Ok global thanks will check this today and get back with results on both checks.

 

If your fuel pump primes with the key on, your pump is working, it's your injectors and ignition that is not.


Again.....Check your ECU for codes.......

Here is a link to testing the CKP, TDC and CYP sensors that are associated with the ECU and fueling. TDC, CKP, CYP sensor testing for No start

And here is a test for the Ignition control module Honda ignition control module (ignitor) test says it is for a Civic but they are the same test procedures.

 

sup bro been awhile since posted anything in regards to the issues i was having,well managed to gather some more patience to help myself to focus but cant seem to know where or what to look at, basically injectors are not pulsating and cel light remains on even after pump has primes, however ive done majority of the obvious things and when noid light check injector plugs noid light flashes as engine is cranking, have spark and fuel pressure what i dont have is tachometer working as motor is cranking, cel light remains on after 2sec. If something combustible sprayed into t.b car fires up immediately. So what do you think i need to check or test ?? Didn't want to repeat this criteria again on forum why i messaging you directly apologize for 20 paragraph message just trying to figure out this issue and also how the process works regarding the cel light when ignition turned on, what is the process happening that ends with it going off after 2sec mark cause i have spark so signal to know when to discharge coil is working, noid lights flash on injector signals and fuel pump primes so whats not allowing the cel light to turn off ?? Anything you can think to check as too whats needed input and output wise to run ive done research and hayes manual but again everything checks out stumped on this.

 

Sup bro been awhile since last shared issues with my accord but didnt want to beat a dead horse with issues having, codes in ecu was only i.a.t sensore code everything else has checked out, wondering if there some order of input/output test to do ? Has spark,fuel pressure and noid light test on injector plugs passed with flying colors and yet injectors aren't pulsating and tach doesn't move during cranking? All fuses have been checked and power confirmed at injector plugs and dist. So what should i be looking for that takes place whenever ignition turned on and cel light turns off after 2sec ? Honestly to the point of going ape **** on this car cause the common problems associated with what signs are being shown aren't what others were experiencing like fuel pump primes and noid light test passes but injectors not pulsating!!!! Smh sorry for the essay,appreciated any info you could give me.

 

Does anyone on this site know the sequence of events between moment ignition turned on × main relay and ecu ?? This would be greatly appreciated to help me figure out whats wrong with my accord as opposed to explaining and geting backwards questions but nothing towards helping with the direction towards causing of problem or maybe this something nobody's ever experienced 🤔 anyways guys to anyone with knowledge of these events and order in which takes place would be much appreciated.

 

Wow the honda game hasnt changed a bit, after all the things achieved and changed with this brand, the crowds around them haven't, unless im the first in entire life of honda has actually asked is there anyone who knows the sequence of events between ignition key- main relay- ecu as for what is needed/verfied for cel light to turn off after 2sec, im not new to hondas but i think regardless or time having/modiying there's a point at which you cant figure out without something/someone give you little help but since ive searched and found similar problems those clearly had signs to what was wrong were as with mine everything is a expected to work except for the issues ive already pleaded for help on different sides of problem and not but 2 - 3 souls attempted to help but with the obvious things to come to mind, but no worries i knew better and not type to bother nor begg, but even just acknowledging with some responses with efforts is appreciated but not one single person on this entire site has not one bit of information regarding issues offered ! Smh thanks to those who gave time and efforts to help.

 

The is a free internet forum. Suggestions were offered, what more can be done?

I know that you normally fix your own cars, but you seem to be in over your head with this one. Maybe its,time to tow it to professionals and let them conduct physical testing and figure out the problem....

 

I don't have access to my Helms manual at the moment for the ignition circuit diagram. If I remember when I wake up tomorrow afternoon I will post up what I have for the startup sequence and what sensors are required.


Where you have tested the distributor sensors (CKP, CYP TDC) and the ICM the only other sensors that I can think of that might cause a fuel cut signal would be the A/T Neutral safety switch (shift position switch) or M/T clutch position switch.

 

your halarious!!! You call 2 or 3 replies asking questions is your definition of suggestions!!!! It's clear you fall right into that category of that type of help, sorry didn't know those who don't fix there own cars are those on this free Honda forum which ironically discuss automotive subjects in this case would be hondas but thanks for informing me about being the only one who fixes there own cars, So exactly what type of things or (if any) kind of advance can you give to anybody if obviously your not the type to work on your own car but respond to those who do ?? Im extremely curious 🤔 to know exactly seeing your classification of me is ????? And aside from this halarious and very interesting character, to the ones who actually know what there talking about and possibly might be like my classification as ( a person that works on there own cars) thanks for your time as i mentioned before.

 

the only code retrieved was for iat sensor which i wouldn't think could interfere with engine starting and as mentioned the ignition system works which is why when starting fluid sprayed into throttle in cranks up immediately, i read somewhere that when certain light come on and go off its indication of certain things example whenever your abs and oil lights come on when ignition turned to on position engine off its confirms ignition is powered and when cel light goes off it confirms ecu has received back its check list of things needed feedback from. Just cant figure out if ignition is making spark at a specific time to specific wires/plugs means coil is being triggered otherwise wouldn't know when to send a spark and if injector plug can operate a noid light showing ground side switch activates it on and off why isnt it doing same to injectors?? It can only be something of short to something possibly not strong enough to prevent a noid light from working but not strong enough ground signal for injectors??? Im gonna do some short to ground testing on injector wires and check for ground connections around ecu cause. Already cleaned and recleaned harness ground, will get back soon with results.

 

I dont even understand this.

Good luck bud.

 

What exactly are you referring too ? My issue with figuring out possible cause of injector issues or the response to the character whom doesn't work on his own car ? But either case that response is expected, when problems of this complexity are involved.

 

Be nice. If the noid lights blink those injectors are firing upon command from the ECU. I cannot follow your posts. It sounds like you think the injectors are not firing.

Pull the rail. Point the injectors up in the air. Get video recorder out hit record. Turn key. I wanna see.

If the pump is working at all, we will see 4 plumes...

 

well got to thinking of possibility that what it takes to pulsate a noid light and what it takes to pulsate an injector might be on different levels of input needed to execute or even on a individual basis vs group of 4 complete circuit with +pos be linked to them all. Ive seen similar problems that whenever one there be one unplugged the interference to ecu's ground signaling would stop if this makes since, trying to see if within engine circuit or else where is there some short to ground happening thats getting tied back to ecu preventing the injector ground signal from happening or strong enough to make happen ?