haha whats that, I would not even know where to begin with that, Justin. I guess from the diagram (which I am not very good at reading circuits) the IGT1 goes straight to one of the coils I guess on cylinder #1?
P1300 and P0300
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Originally Posted By: JustinC25
I'd try running a new IGT 1 wire and piggy back it onto the existing wire with scotch locks and see if that fixes it.
That's a great idea... Had a similar problem on a Buick and we did just this. It fixed the problem and so we just cut the original wire, soldered in the replacement and insulated it with heat shrink tube.
Good Advice
I'd try running a new IGT 1 wire and piggy back it onto the existing wire with scotch locks and see if that fixes it.
That's a great idea... Had a similar problem on a Buick and we did just this. It fixed the problem and so we just cut the original wire, soldered in the replacement and insulated it with heat shrink tube.
Good Advice
I had the same issue on dad's plow truck.
'89 Toyota 4x4 V6. Standard ignition system w/distributor.
Intermittently it would die, no codes (OBD I) Traced it to a bad IGT wire between the ecm, and the igniter. Replaced the wire, and cut the old one, and It ran fine. Still runs fine, and it's been 6 years since the fix.
I'm gonna post the EWD for this circuit for you soon.
Toyota EWD's are the easiest to read.
'89 Toyota 4x4 V6. Standard ignition system w/distributor.
Intermittently it would die, no codes (OBD I) Traced it to a bad IGT wire between the ecm, and the igniter. Replaced the wire, and cut the old one, and It ran fine. Still runs fine, and it's been 6 years since the fix.
I'm gonna post the EWD for this circuit for you soon.
Toyota EWD's are the easiest to read.
Here is a video of a Scotch Lock connector and how to use it:
http://www.wonderhowto.com/how-to/video/how-to-use-scotch-lock-wiring-connectors-164466/
http://www.wonderhowto.com/how-to/video/how-to-use-scotch-lock-wiring-connectors-164466/
IGT 1 runs from the ECM to the Igniter.
Ok. You are looking for a blue wire with a black stripe.
It is in the ecm connector at pin #24, and at the Igniter connector at pin #7 The connectors you want are E8 for the ECM, and I2 for the Igniter. There is a picture of these connectors on the last page of the EWD I'm listing here.
Here is the link to the EWD:
http://www.mediafire.com/?sharekey=0fd1dbbcac08fc91e7c82ed4b8f0c380dd4973ee80fb5b189b20786b9a6e1ed0
I've also included instructions on how to read the ewd, in another pdf on that link. And finally, I included a PDF with the connector locations.
First look at the How to read the ewd document, then read the ewd and the location chart, and you should be golden to fix that wire.
I'm confident after you fix that wire, your code will go away.
Let us know how you make out.
Ok. You are looking for a blue wire with a black stripe.
It is in the ecm connector at pin #24, and at the Igniter connector at pin #7 The connectors you want are E8 for the ECM, and I2 for the Igniter. There is a picture of these connectors on the last page of the EWD I'm listing here.
Here is the link to the EWD:
http://www.mediafire.com/?sharekey=0fd1dbbcac08fc91e7c82ed4b8f0c380dd4973ee80fb5b189b20786b9a6e1ed0
I've also included instructions on how to read the ewd, in another pdf on that link. And finally, I included a PDF with the connector locations.
First look at the How to read the ewd document, then read the ewd and the location chart, and you should be golden to fix that wire.
I'm confident after you fix that wire, your code will go away.
Let us know how you make out.
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Justin- Thanks for your help. I am going to double-confirm that my readings were correct and that in fact it really is the IGT-1 Circuit. From there on, I am a bit worried about damaging the wiring harness by tapping into it, as the wires are old AND thin.
The scotch lock will tap into it without damage. (see the video I posted previously) Just make sure to do it away from the connector. So that if you need to to make it permanant you have some wire to solder to.
I'd probably place the scotch lock back about 4-5" from the connector for this purpose. Also make sure to look at the EWD, before going back to verify the IGT-1 circuit. That way you can see which wire it is.
Let us know how you make out.
Justin
I'd probably place the scotch lock back about 4-5" from the connector for this purpose. Also make sure to look at the EWD, before going back to verify the IGT-1 circuit. That way you can see which wire it is.
Let us know how you make out.
Justin
Justin-I will try it...I watched the scotch lock connector video previously and it does puncture the wire correct? I mean it has to to make the connection right? So, just to make sure i understand this...I will need 2 scotch connectors--1 by the connection to the ECM and one by the connection at the igniter. So in essence I am bypassing the blue and black wire altogether, but using just one point on that wire to tap into so I do not have to go through undoing the wires from the connector to run a new wire.
OK, during lunch I took the car out and CEL came on again, same code. Plus, the last few times the CEL came on it will idle low like it is going to stall, then after like 10 secs it is back to normal. I looked at the EWD quickly and saw the blue and black wire right where it is supposed to be on the igniter harness. I bought the Scotch-Lock connectors at Home Depot. Tonight I will confirm the diagnosis when I take the glove box out...WISH ME LUCK!
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LUCK
ONE MORE THING, Justin- I have different gauges of the scotch-lock connectors...which gauge should I use?
OK so I reverified everything I checked last night, and good thing I did. All circuits checked out fine. Last night I was one pin off when I was checking, making that reading erroneous. All the circuits checked out, so I think I should probably leave it as is for now, until it gets much worse.
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Originally Posted By: parimento1
OK so I reverified everything I checked last night, and good thing I did. All circuits checked out fine. Last night I was one pin off when I was checking, making that reading erroneous. All the circuits checked out, so I think I should probably leave it as is for now, until it gets much worse.
It sounds like you are having an intermittent problem here. You already changed the Igniter, and ECM correct ?
If so, then the only other thing it can be is wiring per the flow chart. What tests did you do on the IGT-1 wiring to verify the problem ? Did you just check for continunity, or test the voltage from the ecm to ground by back probing the IGT-1 connector on the ecm ? Also if you don't have a back probe, you can make one with a sewing pin, or needle, a piece of wire, and a soldering iron. Just solder the wire on to the pin or needle. I still have a feeling that the issue is coming from IGT-1. IGT is the signal from the ecm to the igniter to fire the coil. Code P1300 is triggered by no IGF signal from the igniter for 6 consecutive cycles. IGF is the return signal from the igniter to the ecm to confirm that it got the message. So if the igniter is not getting the signal to fire, then it won't send it back to the ecm. There by triggering your code, and the misfire you felt.
I think we need to go back to basics, and run through that diag flow chart again from scratch.
Don't worry, we'll get this. It might take a little more time, but we are so close.
Justin
OK so I reverified everything I checked last night, and good thing I did. All circuits checked out fine. Last night I was one pin off when I was checking, making that reading erroneous. All the circuits checked out, so I think I should probably leave it as is for now, until it gets much worse.
It sounds like you are having an intermittent problem here. You already changed the Igniter, and ECM correct ?
If so, then the only other thing it can be is wiring per the flow chart. What tests did you do on the IGT-1 wiring to verify the problem ? Did you just check for continunity, or test the voltage from the ecm to ground by back probing the IGT-1 connector on the ecm ? Also if you don't have a back probe, you can make one with a sewing pin, or needle, a piece of wire, and a soldering iron. Just solder the wire on to the pin or needle. I still have a feeling that the issue is coming from IGT-1. IGT is the signal from the ecm to the igniter to fire the coil. Code P1300 is triggered by no IGF signal from the igniter for 6 consecutive cycles. IGF is the return signal from the igniter to the ecm to confirm that it got the message. So if the igniter is not getting the signal to fire, then it won't send it back to the ecm. There by triggering your code, and the misfire you felt.
I think we need to go back to basics, and run through that diag flow chart again from scratch.
Don't worry, we'll get this. It might take a little more time, but we are so close.
Justin
Yes, I replaced the ECM, igniter, coils, plugs and wires. To verify the diagnosis, I followed the flowchart and checked the voltage at IGT 1-3 at the computer pins with the engine cranking, with both the igniter connected and disconnected, and got normal voltage from all 3 circuits. I also did the check to make sure there was good voltage to the igniter and an IGF signal voltage. I looked at the wiring next and like I said, the only thing I could find was that little rubbed off area on one of the igniter wires. I covered it with electrical tape and no change. What I don't get is how can the wiring be faulty if it is covered in conduit and then wrapped in electrical tape. I pulled apart the battery and starter wires from their conduit and it looked brand new and nice and pliable. I looked at your post and I do not know what back probing is. Just as a side-note... I took it to the dealer many moons ago and they could not track down the problem, even with a regional technician that they flew in to look at the problem.
Now that I think of it...Can a "kill switch" that is not functioning correctly cause this problem. The guy who installed the keyless entry in my car installed an aftermarket kill switch, which I assume is tapped into the ignition system somewhere.
Originally Posted By: parimento1
Now that I think of it...Can a "kill switch" that is not functioning correctly cause this problem. The guy who installed the keyless entry in my car installed an aftermarket kill switch, which I assume is tapped into the ignition system somewhere.
You might have just solved your problem! I would be following all the wires from that module and checking the connections.
Now that I think of it...Can a "kill switch" that is not functioning correctly cause this problem. The guy who installed the keyless entry in my car installed an aftermarket kill switch, which I assume is tapped into the ignition system somewhere.
You might have just solved your problem! I would be following all the wires from that module and checking the connections.
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