1JZGTE Code 14

YYCSupra

YYCSupra

Getting back in the game
Aug 4, 2014
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Alberta
Hi guys,
Could use a bit of help on trouble shooting this...:1zhelp:
I am getting code 14 after driving for about 7-8 miles (or 15min of driving). Car will drive somewhat fine until it reaches operating temperature then once I start stopping at traffic lights it will start to act up. When it acts up, the CEL will flash and the car will start bucking and the idle will drop to about 400 for a bit then pop back up (sometimes it can be very erratic). The car will become almost impossible to drive as it will buck like crazy. To drive I need to park the car for 5-10 minutes, then the car will start up just great and I'll be able to drive it about a mile or so before the symptoms come back. This seems to tell me it has something to do with heat. Car temperature and oil pressure is spot on. Car is basically stock w/ stock twins.

Another issue, although not sure if this is related, but my fuel pump relay (passenger side on LHD car) buzzes sometimes. I bypassed the fuel pump relay by jumping couple pins in the check connector (with really no difference). Local shop who specializes in supras thinks i might be hitting fuel cut but they haven't experienced the symptom yet so they are just going from my description.

I'm thinking it's either my igniter or my ECU is done. From what I've been able to read, code 14 is typically very specific to IGF. Today I'm going to check my CAM position sensors to see if they are within spec as per 2jz TSRM.

What I've checked so far:
I sent my ECU in to DM for Capacitor replacement in December (had one leaking cap).
Checked voltage to igniter and it was almost spot on (12v).
Checked voltage of IGF wire to igniter and it was within spec (about 4.5v as per 2jz TSRM)
New 2jz Denso coil packs installed (my old ones were cracked)
New spark plugs (also tried my old spark plugs w/ no difference)
Water temp sensor is within spec
Checked new coil packs and all are within spec 0.8ohm
New coil pack connector clips
 
Last edited:
hvyman

hvyman

Dang Dude! No Way Man.
Staff member
Apr 17, 2007
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could be cam or crank sensors or the igniter. the cam sensors like to get filled with oil.
 
YYCSupra

YYCSupra

Getting back in the game
Aug 4, 2014
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I was having issues finding the Crank Sensor cause I was going to clean that one too. Where is the Crank Sensor on the 1J? My Cam Sensors were both quite oily. I blasted them both with brake cleaner and then used compressed air to clean them out. Did the same for the connector.

I drove the car tonight and after about an hour the CEL came on for a few seconds and my idle dropped, but as soon as I pulled over the CEL went out and my idle returned to normal. I drove for another 15min or so and it was fine. It was the longest I'd driven without having the car buck like crazy on me. When I got home I checked for a code but got none.

Quick question, but if I do the 12V mod does it bypass my fuel pump relay and resistor? When I was driving my relay was buzzing, but it didn't seem to make a difference on how the car was driving. Seemed to eventually stop after 45 mins or so.
 
hvyman

hvyman

Dang Dude! No Way Man.
Staff member
Apr 17, 2007
12,568
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0
Fullerton,CA
The 12v mod bypasses the resistor not the relay. The relay could be making noise but depends on how te car is wired or is this a factory 1jz car?

Also based off that clearing things up by cleaning the cam sensors I would say that is most likely your problem.

Crank sensor mounts on exhaust side of oil pump by crank pulley. Connector is near O2 sensor connector.
 
YYCSupra

YYCSupra

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Aug 4, 2014
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It snowed today so I couldn't do any more test drives...My car is a left hand drive with a 1JZ transplant completed by driftmotion. To get at the Cam Sensors, do you have to remove the intake? I'm not standing by my car, but I would think I would have to remove the IACV for sure?
 
f00g00

f00g00

Supramania Contributor
Jul 2, 2007
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Kuwait
You can remove them without removing the intake.There are two bolts holding them on so you might want to put a rag underneath in case one drops.
The cam and crank sensors are more for code 12 and 13. The motor will run fine with only one cam sensor signal (at least mine did) and won't run at all without the crank sensor.
I would check connector and wires on the igniter and ecu. Sometimes the wire connections at the ecu move and cause weird stuff to happen. You might also inspect the female pins on the harness to ecu plugs. If the pins look like they are open too much it might cause a connection problem. Also make sure the wires are secured properly behind the dash and lined up with the ecu and not drooping.
 
YYCSupra

YYCSupra

Getting back in the game
Aug 4, 2014
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Alberta
Great advice F00g00, I'll have a look next time. I did have to solder a wire that goes to my igniter. I soldered it pretty well and then used heat shrink on it. Do you think that might cause my problem? I brought the car to a local shop and they re-soldered it just in case and used heat shrink as well and I was still getting issues. I'm wondering if the heat shrink isn't shielding the wire from the engine heat well enough. The wire I soldered wasn't the IGF wire though (can't remember which now). I wish I had an ECU pin out for the JZA70 supra so I could figure out what pin on the ECU is the IGF wire so I could check it.
 
YYCSupra

YYCSupra

Getting back in the game
Aug 4, 2014
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In the image below it seems to say that if you are getting 4.5-5 volts on the IGF wire that you should replace the igniter. Is that correct? When I did this test at home I got 4.5v. Can someone please explain the step three in the picture, I'm not sure I'm doing it right? I tested IGF from the igniter harness (leaving ECU connected), with the ignition on and I got 4.5v. In the picture, the harness looks different than mine (if it's supposed to be the igniter harness).
Thanks for the help.

ignitor.JPG
 
YYCSupra

YYCSupra

Getting back in the game
Aug 4, 2014
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So I got another igniter and it is still doing the same thing. I think it must be my ECU. I'm going to check the continuity of my cam and crank sensor wires then I'll start looking at ECU replacement options. I checked the continuity of all the wires between my ECU and igniter as well as between my igniter and my coil packs. Everything checked out as 0.02 ohms. I really didn't want to go standalone this soon, but may have to, ugh!
 
YYCSupra

YYCSupra

Getting back in the game
Aug 4, 2014
128
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Alberta
I've tried jiggling cables when I was having the issue and I haven't had much luck with it (car runs great when cool, only have the issue once it's warmed up). I know which wires connect the two as I did a continuity test on them. The weird thing is that the last 5 times I've had the problem, it hasn't left a code at all (not even code 14). The resistance values on my cam and crank sensors were within spec as per the 2JZ manual. All the wiring and pins seem fine. Car was also kind of doing a bit of backfiring when I was shifting. Nothing really loud, but a bit sparky sounding.
 
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