LS/Vtec, No Spark!? help
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LS/Vtec, No Spark!? help
Got motor in, wiring in place, ecu hooked up. Cranked it over and it didn't start smelled something like wires burning, and I craked open the ecu case and a small amount of smoke came out. Noticed there was a small char in the top left corner of my ecu. Called the guy who chipped and tuned my car, and he said that I had my iat and evap purge selonoid sensor plugged in backwards. That the iat was 2 wire and was supposed to be red and green. He stated that my ecu should still be good, however my iat probably isnt, charred transistor q31. Well my iat plug isnt melted or anything and the prongs still look good no damage, swithced them back, and now i simply have crank, but no start.
it has new plugs, plug wires. the distributor im pretty positivie is fine, as it worked just fine on the car that it came off of, any help would be appreciated, i have fuel getting to the combustion chamber, just no spark.
my setup is a b18a1 with a b16a3 head and manifold. i have all 3 grounds as well.
any help would be appreciated.
it has new plugs, plug wires. the distributor im pretty positivie is fine, as it worked just fine on the car that it came off of, any help would be appreciated, i have fuel getting to the combustion chamber, just no spark.
my setup is a b18a1 with a b16a3 head and manifold. i have all 3 grounds as well.
any help would be appreciated.
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Re: LS/Vtec, No Spark!? help
Although you can see the visible damage to the board because of the burnt transistor, that still doesnt determine what else might have gone wrong with it.
If it burned, then most likely it received a power surge that it doesn't normally get. Even if you replace the transistor, there are other components on the ECU that might have shorted also, and you wouldn't know by a visual inspection.
I wouldn't trust that the ECU is still good. You can try to replace the resistor, but if your car still acts up, I would try swapping the ECU's with a friends and see if you still have the same problem.
And please don't go around touching the components on the circuit board while inspecting them. Remember, it only takes 5 volts to compromise the circuit in a component (the static electric shock you get from door handles is 50,000 volts, so you can pass a static electric charge and not even know)....just a little FYI.
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Re: LS/Vtec, No Spark!? help
yeah, im a believer in that the ecu might be shot. I know that the distributor is good so i dont think that that is the issue. do places like autozone, napa have a way to test the ecu. or is there another way to test the ecu.
#5
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Re: LS/Vtec, No Spark!? help
Sounds like your ECU is damaged.
And you have to swap it with a working ECU and test it that way. I'm sure Honda engineers can test the ECU but who are we kidding here; unfortunately, they don't offer that service.
And you have to swap it with a working ECU and test it that way. I'm sure Honda engineers can test the ECU but who are we kidding here; unfortunately, they don't offer that service.
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Re: LS/Vtec, No Spark!? help
so i just cleaned up all my grounds, making sure it was clearly metal to metal contact. I know all of my connections are good. yet still no spark.
it is the ecu right?
if so does anybody have an obd1 p72
or a p28 with a jumper harness
it is the ecu right?
if so does anybody have an obd1 p72
or a p28 with a jumper harness
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Re: LS/Vtec, No Spark!? help
ok so update,
i had borrowed somebody else's ecu, p75. i know its a non-vtec ecu. but my ecu wires arent run though yet so it should start my engine, it may make it run rough, but it should start it.
well turns out that didnt work. we are not getting spark. my main relay is good, grounds are good, however no spark. so we changed the coil pack and still nothing.
for what its worth almost nothing in the interior works, like my headlights, wiper switch, the dome light does work along with the radio and the climate control lights up.
i need assistance or any input
i had borrowed somebody else's ecu, p75. i know its a non-vtec ecu. but my ecu wires arent run though yet so it should start my engine, it may make it run rough, but it should start it.
well turns out that didnt work. we are not getting spark. my main relay is good, grounds are good, however no spark. so we changed the coil pack and still nothing.
for what its worth almost nothing in the interior works, like my headlights, wiper switch, the dome light does work along with the radio and the climate control lights up.
i need assistance or any input
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Re: LS/Vtec, No Spark!? help
ok so i bought a haynes manual, and did some diagnosing.
discovered that inside the distributor, there is a black/yellow wire coming from the ICM (ignition control module), that goes to the coil pack that is not receiving the proper voltage. Coil pack is good - tested it with a multimeter, and the icm is brand new. could that wire just be bad, or is it fuse related??
discovered that inside the distributor, there is a black/yellow wire coming from the ICM (ignition control module), that goes to the coil pack that is not receiving the proper voltage. Coil pack is good - tested it with a multimeter, and the icm is brand new. could that wire just be bad, or is it fuse related??
#12
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Re: LS/Vtec, No Spark!? help
If nothing in the interior works, you've probably blown your main fuse. It's a big *** one inside the panel under the hood. You would still be able to crank the car because the starter power comes directly from the battery. Blown main fuse means pretty much everything isn't getting juice.
Check all fuses.
Check all fuses.
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Re: LS/Vtec, No Spark!? help
some things do work in the interior though, like the radio, cd player and the climate control lights up.
but maybe ur right.. is there a way to chek the main fuse?
but maybe ur right.. is there a way to chek the main fuse?
#14
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Re: LS/Vtec, No Spark!? help
Yes the top of it is clear and you can see if it's been blown. You should be checking all of your fuses, in car and under the hood. It's easy and it rules out something as silly as a blown fuse. With Hondas it's always something stupid. Everything is pretty solid and reliable as far as components go.
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Re: LS/Vtec, No Spark!? help
Is there a diagram that says which fuse is which, my car conviently didn't come with one. I have the one for under the dash, but not the one under the hood
#16
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Re: LS/Vtec, No Spark!? help
What do you mean your car didn't come with one? You mean the fuse is missing from it's slot? We're talking about the same thing right? Little black box under the hood, full of fuses. If the fuse is missing, then that is your problem my friend. Go get a new fuse.
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Re: LS/Vtec, No Spark!? help
No the diagram saying which fuse is which, I have all the fuses. Just don't know which one is which. That's what I meant. Sorry for the confusion.
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Re: LS/Vtec, No Spark!? help
ok so i checked all my fuses. they are all in good shape.
but for some reason, when checking them and doing some diagnosing, i noticed that my fuel pump no longer primes itself, could being low on fuel cause this?
and that black/yellow wired inside my dizzy run to my alternator as well, could it simply be that i might have a bad alternator that is preventing me from getting spark. i read in that haynes manual that the alternator helps to provide power to the dizzy, and that there is also a fusible link in some alternators, and if it goes bad it wont allow some accesories to work, and prevent the engine from start, but where is it at?
help is appreciated
but for some reason, when checking them and doing some diagnosing, i noticed that my fuel pump no longer primes itself, could being low on fuel cause this?
and that black/yellow wired inside my dizzy run to my alternator as well, could it simply be that i might have a bad alternator that is preventing me from getting spark. i read in that haynes manual that the alternator helps to provide power to the dizzy, and that there is also a fusible link in some alternators, and if it goes bad it wont allow some accesories to work, and prevent the engine from start, but where is it at?
help is appreciated
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Re: LS/Vtec, No Spark!? help
yeah that is the next issue i am going to elimante, and hopefully it will solve the problem. i have the charger hooked up to it now, and it is charging on a deep cycle. checked to see if the fuel pump primes now, and it does.
will the battery being low, cause me to get no spark at all?
when we tested the black/yellow wire it showed about 3.2v and the white/blue showed about 12, so being that the battery may be low, might resolve my issues i think.
any input on that?
will the battery being low, cause me to get no spark at all?
when we tested the black/yellow wire it showed about 3.2v and the white/blue showed about 12, so being that the battery may be low, might resolve my issues i think.
any input on that?
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Re: LS/Vtec, No Spark!? help
Ok so I got a repair manual also, checked the location of every single fuse, and wether it was good or bad. So that is squared away.
Yet I'm still lacking spark.
Ideas????
Yet I'm still lacking spark.
Ideas????
#22
Re: LS/Vtec, No Spark!? help
Have you checked the YEL/GRN wire attached to the igniter unit/ICM for an open or short? Is the CEL ON?
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Re: LS/Vtec, No Spark!? help
I promise, the blk/ylw wire goes to the positive side of the coil pack, and it only shows .5-3.2v. While the wht/blu wire shows battery voltage.
Ok so I may have a bigger issue with it being the incorrect dizzy. Inside I originally thought we had three different color wires. Now it looks as though we only have three, yellow/green and black/yellow, and blue. I assumed that one of the wires had just gotten dirty with age. Could that be my problem. Cel is on but I do not have an o2 sens.
If so what dizzy do I have? There is a tiny etching on the inside of it that says p06, just an FYI
Ok so I may have a bigger issue with it being the incorrect dizzy. Inside I originally thought we had three different color wires. Now it looks as though we only have three, yellow/green and black/yellow, and blue. I assumed that one of the wires had just gotten dirty with age. Could that be my problem. Cel is on but I do not have an o2 sens.
If so what dizzy do I have? There is a tiny etching on the inside of it that says p06, just an FYI
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Re: LS/Vtec, No Spark!? help
Ok so. We made a breakthrough. Turns out that the connector coming from the dizzy containing the blk/ylw + blue wire, were backwards. Meaning blk/ylw to blue and blue to blk/ylw. Nothing we did just the way the two were. We switched them and now we have spark!!! Finally.
But as u would have guessed still no start. Gas is good, level is fine, fuel pump primes nice and good, injectors are good; I tested their resistance. And now what?
Does this all go back to the possibility of my ecu being bad?
But as u would have guessed still no start. Gas is good, level is fine, fuel pump primes nice and good, injectors are good; I tested their resistance. And now what?
Does this all go back to the possibility of my ecu being bad?
#25
Re: LS/Vtec, No Spark!? help
What color is the spark at the plugs? Is it bright white-bluish or weak orange in color? Are the plug wires connected in the correct firing order?
Do you measure battery voltage on the power wire for the fuel injectors?
Pull the CEL codes from the ECU as new ones may now be stored there.
Do you measure battery voltage on the power wire for the fuel injectors?
Pull the CEL codes from the ECU as new ones may now be stored there.