Had some wiring issues with my harness that woould blow efi fuses. I took the harness off, had it all redone and reinstalled it. Now the car starts, but shuts right back off. I cannot check codes because the diagnostics box isn't hooked up. The car ran last night for a few minutes, I could turn it on, and then back off, and back on again. But when I was ready to test drive it, it started messing up. The car starts and runs for like a second and shuts back off.I unplugged the coolant temp sensors to see if maybe they were bad and it does the same thing. Any suggestions?
1jz issue
- Thread starter Bucsfanatic59
- Start date
hey man long time no see. Is this in the red car?
anyhow, is it throwing any codes? do you have a solid e2 ground? sometimes the map sensor doesn't like a shity ground. make sure you have 4.8-5v on VC (yellow wire) good ground on e2 (brown wire) and a signal on the PIM wire (green wire) this wire should only be continuous to the ecu with no shorts or other connections. If the map isnt making a signal it will cut fuel right away kind of like an unplugged maf. You're still getting fuel during cranking and it's probably just firing off of that.
It could also be the cold start not giving wnough fuel right away? Make sure the black wire from the cold start is continuous to STA. Or just spray carb cleaner in there and try to idle it that way until it warms up
So yeah, sorry if I just complicated things for you. Go check that sensor ground haha.
good luck.
anyhow, is it throwing any codes? do you have a solid e2 ground? sometimes the map sensor doesn't like a shity ground. make sure you have 4.8-5v on VC (yellow wire) good ground on e2 (brown wire) and a signal on the PIM wire (green wire) this wire should only be continuous to the ecu with no shorts or other connections. If the map isnt making a signal it will cut fuel right away kind of like an unplugged maf. You're still getting fuel during cranking and it's probably just firing off of that.
It could also be the cold start not giving wnough fuel right away? Make sure the black wire from the cold start is continuous to STA. Or just spray carb cleaner in there and try to idle it that way until it warms up
So yeah, sorry if I just complicated things for you. Go check that sensor ground haha.
good luck.
did you extend your harness or did you just simply pull i through the speedo hole.
sounds like your overloading the fuse with a short or you may have blown your ecu and have a short in it?
remove your ecu does it blow then if it does the short is in the harness you can pull codes by going to the grey/green wire on the T connector.
sounds like your overloading the fuse with a short or you may have blown your ecu and have a short in it?
remove your ecu does it blow then if it does the short is in the harness you can pull codes by going to the grey/green wire on the T connector.
Thanks guys, I'll check these things.... The harness has been extended. When we did it the first time, it got melted and would blow efi fuses when I started it. Now that it was cut and re-extended its not blowing fuses. The map sensor doesnt touch any metal or anything like that, dont think it ever did, so if its gorund is it ground through the plug or it needs to be against metal and bolted down?
The map sensor has three wires: ground (E2), 5v (VC), and 0-5v signal out (PIN). THe bracket has nothing to do with ground. The ground to the map sensor is not chassis ground, it's a ground output from the ECU.
Check this out, it should help:
http://www.1jz-gte.us/documents/SubDocs1/WiringEFI.pdf
Check this out, it should help:
http://www.1jz-gte.us/documents/SubDocs1/WiringEFI.pdf
^ Thanks..I have no idea what it can be then. I'm gonna go play around with it more tomorrow and start checking volts to things and fuel, I know its getting spark and I assumed fuel cuz I smelled it. The map sensor sat in the car for 2-3 months, maybe it went bad, or maybe the ecu got fried.....There only one other running mk3 with a 1jz around here, so I need to convince her to let me plug in my ecu into her car or something...
When extending an engine harness, people often make the mistake of cutting a bunch of wires at a time, only to notice later on that there are many wires that are the same color and gauge. It's always best to do one wire at a time, then there is no room for error.
bigaaron said:
Definitely good, solid advice here. This can also help prevent the "softball" formation that some people get when they don't stagger their splices [their girth makes the connecting points add up and get huge!].
If you DO extend by cutting all at once, the best advice I have for you is to buy a roll of masking tape and a permanent felt-tipped marker - that way, you can mark both sides of each clipped wire.
^^ Agreed allways stagger also if 2 or more wires come apart when staggered they will not short out on each other. gets rid of the big rat in the middle of the snake look also.
1ST method
instead of using big crappy auto butt splices or barrel splices
use MIL spec enviromental splices that you use a sargent or dmc ratchetting crimper to percisionely crimp.
Then using a air heat gun to shrink the hard plastic emviromental splice around the wire until the resin inside comes out the edges as an indicator so you dont burn the wire or enviromental shrink, but you want the resin to reach the edge to be sure you spliced it!
Also use the mil spec shield jumpers for the shielded wires.
2ND method
bearly passable
solder the two wires together at a minimul length of 3X the thicknes of the wire but no more then 10x the thickness of the wire in length but make sure not to move the wires when melted then when cooled tug on them you dont want a cold joint, if they come apart after tugging redo it until you pefect this. Then with your shrink tubbing slide the sleeve over that bearly slides over the wire and the solder connection thickness then shrink it down.
but the problem is it is hard to do shield jumpers unless you know exactly what i mean this method.
Do not extend the sensitive shielded wires without shielding them the rest of the length!
Because verry sensitive micro voltage signals are red and sent to the engine cross noise from these or other extanal inteference can cause severe ecu damage severe engine damage and at least cause poor performance!
Do not do what your radio instalation people do and twist 2 copper wires together and electrical tap them together only twisted.
Do not cut them at the same length
in best case scenario it is almost identical to factory so if there is a flaw from extending the harness as compaired to simply pulling the wires through the speedo hole instead then dont be supprised.
It is not as simple as it looks to splice each wire 2X before it gets to the ecu and do it the way it would come from factory the only way you could do this by splicing 1X is if you use 2 harness and clip them where you get more then the extra 2 feet you need then splice the two longer parts together
This is why i recemend leaving the elecetrical factory and pulling it through the speedo hole the speedo hole is already there and works for mounting the ecu factory location and it takes about 5 min to make the speedo hole slightly larger where as extending each wire could add more then 3 days to your engine swap.
1ST method
instead of using big crappy auto butt splices or barrel splices
Then using a air heat gun to shrink the hard plastic emviromental splice around the wire until the resin inside comes out the edges as an indicator so you dont burn the wire or enviromental shrink, but you want the resin to reach the edge to be sure you spliced it!
Also use the mil spec shield jumpers for the shielded wires.
2ND method
bearly passable
solder the two wires together at a minimul length of 3X the thicknes of the wire but no more then 10x the thickness of the wire in length but make sure not to move the wires when melted then when cooled tug on them you dont want a cold joint, if they come apart after tugging redo it until you pefect this. Then with your shrink tubbing slide the sleeve over that bearly slides over the wire and the solder connection thickness then shrink it down.
but the problem is it is hard to do shield jumpers unless you know exactly what i mean this method.
Do not extend the sensitive shielded wires without shielding them the rest of the length!
Because verry sensitive micro voltage signals are red and sent to the engine cross noise from these or other extanal inteference can cause severe ecu damage severe engine damage and at least cause poor performance!
Do not do what your radio instalation people do and twist 2 copper wires together and electrical tap them together only twisted.
Do not cut them at the same length
in best case scenario it is almost identical to factory so if there is a flaw from extending the harness as compaired to simply pulling the wires through the speedo hole instead then dont be supprised.
It is not as simple as it looks to splice each wire 2X before it gets to the ecu and do it the way it would come from factory the only way you could do this by splicing 1X is if you use 2 harness and clip them where you get more then the extra 2 feet you need then splice the two longer parts together
This is why i recemend leaving the elecetrical factory and pulling it through the speedo hole the speedo hole is already there and works for mounting the ecu factory location and it takes about 5 min to make the speedo hole slightly larger where as extending each wire could add more then 3 days to your engine swap.
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Well the car runs now. It starts idles and revs up fine. Every once in awhile I will rev it up and it shuts off. Then it won't start back unless I reset the ecu. The only thing I can think of is that the ecu got messed up when the harness was blowing efi fuses..Just need to test it somehow I guess....
that was my suggestion on SF
justin (tissimo) knows what he is doing so he i know he didn't butcher the harness
justin (tissimo) knows what he is doing so he i know he didn't butcher the harness
^^^ looks like a bad ecu in that case look for caps leaking and swelled up. you can buy a working one on ebay for $100 because people goto stand alone all the time. the cost to fix one is 50-75$ if it can be fixed then with shipping cost and down time go in the FS section and ask for one i guess.
or time for a standalone unit ?
drift motion might have some for sale?
or time for a standalone unit ?
drift motion might have some for sale?
Evilempire1.3JZ-GTE said:
I'll be going aem in a few months, need something to get me by till then.