Fuel Injectors not firing! What would cause this?
07-30-2016, 08:50 PM
#21
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Wiring diagram
I have some great wiring schematics that I can email you. I don't have enough posts to upload but I am willing to share. They are straight from the toyota its system so they are color coded and great. Just used them to fix a ignition issue with mine.
08-02-2016, 08:48 AM
#22
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08-02-2016, 08:54 AM
#23
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You are always going to have rail pressure so long as your fuel pump is working and the test is not to see if the cold start injector is in good shape. It is to see if you are actually getting signal through your injector harness to the injectors. You see, it's the only injector that you can actually hold in your hand while it's doing it's thing. If it works or doesn't work, you are going to really narrow down your list of possible problems.
08-02-2016, 11:34 AM
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UPDATE: I just went out there and ran jumper wires from the battery to the cold start injector and it did spray! So this tells me that I am not getting signal to my fuel injectors nor my cold start injector. What would cause this??
08-02-2016, 12:13 PM
#26
Does anyone know how ecm gets the info to fire the injectors. No cam or crank sensors? The ecm gets it from the distributor right?
08-02-2016, 07:05 PM
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I think it will be something crazy simple also. The only relays and fuses I know for the EFI are the two in the box under the hood, are their more? I will change them out with new ones just to cover my ass. I have checked the timing, it is correct.
08-02-2016, 07:33 PM
#28
No need to replace them if they are good. Yea, it's just the few under the hood.
08-02-2016, 07:59 PM
#29
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ECM will stop feeding the negative signal pulses to the injectors if it's not getting feedback from the igniter. You should have positive signal to them all the time and it takes pulses of ground to close the circuit. I assume that this is the case for the cold start injector as well. You said jumper wires. Try running only a ground wire to the cold start injector and see if it sprays. You did say that you had a positive signal to the injector's with the key on, right?
Find some info on troubleshooting / testing the igniter. They are too expensive to just go and buy one to try but if you know anyone with a truck like yours, you might see if they will let you borrow theirs for a few minutes and see if it doesn't crank. I have a spare in my electrical box that I would send you but I think they changed just a little between my 89 3VZE and your 95. If you can confirm that mine is the same, I would be willing to send it to you to try. A wrecking yard may have one too. It's not much to look at and if they don't know what they cost, you might pick one up for $5 or they may let you take one just to test it out.
Find some info on troubleshooting / testing the igniter. They are too expensive to just go and buy one to try but if you know anyone with a truck like yours, you might see if they will let you borrow theirs for a few minutes and see if it doesn't crank. I have a spare in my electrical box that I would send you but I think they changed just a little between my 89 3VZE and your 95. If you can confirm that mine is the same, I would be willing to send it to you to try. A wrecking yard may have one too. It's not much to look at and if they don't know what they cost, you might pick one up for $5 or they may let you take one just to test it out.
08-02-2016, 08:14 PM
#30
ECM will stop feeding the negative signal pulses to the injectors if it's not getting feedback from the igniter. You should have positive signal to them all the time and it takes pulses of ground to close the circuit. I assume that this is the case for the cold start injector as well. You said jumper wires. Try running only a ground wire to the cold start injector and see if it sprays. You did say that you had a positive signal to the injector's with the key on, right? Find some info on troubleshooting / testing the igniter. They are too expensive to just go and buy one to try but if you know anyone with a truck like yours, you might see if they will let you borrow theirs for a few minutes and see if it doesn't crank. I have a spare in my electrical box that I would send you but I think they changed just a little between my 89 3VZE and your 95. If you can confirm that mine is the same, I would be willing to send it to you to try. A wrecking yard may have one too. It's not much to look at and if they don't know what they cost, you might pick one up for $5 or they may let you take one just to test it out.
08-02-2016, 09:00 PM
#31
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https://www.yotatech.com/forums/f2/n...89-95-a-10543/
I just did a search on igniter test. Looks like a lot of good info here. I'd read through it all but my truck is running fine so I'll leave that to you fellers.
I just did a search on igniter test. Looks like a lot of good info here. I'd read through it all but my truck is running fine so I'll leave that to you fellers.
08-02-2016, 10:46 PM
#32
https://www.yotatech.com/forums/f2/n...89-95-a-10543/ I just did a search on igniter test. Looks like a lot of good info here. I'd read through it all but my truck is running fine so I'll leave that to you fellers.
08-05-2016, 11:40 AM
#33
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ok, I just was able to get back to testing this 4runner again and my distributor did fail a test, it failed the ohms test between G and NE, so hopefully this is it. Will replace distributor and go from there. Thanks so much for the link!!!
08-09-2016, 02:04 PM
#34
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well ˟˟˟˟, new distributor didn't do the trick, and it tested out the same as my old one, so I guess it wasn't bad. Went ahead and did the rest of the tests and passed everything. I'm lost again!!! This 4runner was running great, it threw a knock sensor code and I changed it with one from the dealership and put it all back together, and haven't been able to start this thing yet.
08-09-2016, 02:08 PM
#35
well ˟˟˟˟, new distributor didn't do the trick, and it tested out the same as my old one, so I guess it wasn't bad. Went ahead and did the rest of the tests and passed everything. I'm lost again!!! This 4runner was running great, it threw a knock sensor code and I changed it with one from the dealership and put it all back together, and haven't been able to start this thing yet.
08-09-2016, 05:10 PM
#36
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08-09-2016, 05:42 PM
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i literally just had an issue loosing fire. cylinder 3 and cylinder 6 would randomly not fire. that's why I had all the wiring diagrams after testing the g and ne ohms, the air gap and the igniter I was lost. just as a guess and try because no where in the manual does it show a control circuit in the ecu for the ignition firing. after $62.00 for an ecu this thing has never ran better.
08-09-2016, 06:47 PM
#39
It's the little grey box next to the coil. Look on page 2 when we where talking about them. They are crazy expansive(why I was trying to get ur location to borrow my extra). I'm pretty sure they play a part in that circuit. I could be wrong
Icm and ecu talk to each other to coordinate injector pulses?
Icm and ecu talk to each other to coordinate injector pulses?
08-09-2016, 08:50 PM
#40
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I will say that in reading through these posts it just does NOT sound like an injector problem. There are lots of things it could be, but the quick test is with starter fluid. If it won't start with starter fluid, the problem is not the failure of the injectors to open.
