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Vatche
03-07-2011, 03:15 AM
Hi guys, so ive been in the process of upgrading shit on my car. i installed 550cc injectors z32 maf and power fc.

so earlier i was troubleshooting a problem with how my car was running really shitty.

i tested injectors first by unplugging one at a time and nothing changed.

then i pulled the fuel rail and on a paper towel all 4 injectors left same amount of fuel.

so then i assumed it was the maf, like always on my car.(maf wiring SUCKS)

the wires were mixed up (my fault) i bought a multi-meter and test light to do the job right.

tested and found 5v signal wire and 12v constant easily.

i rewired everything and now i get no signal to the signal wire.
(i didnt disconnect the battery because im a FOOL)

power fc also highlights the afrl as 0.0v.

it wasnt highlighted before.

so i was scared that maybe i fried my power fc....

so i put the stock ecu back on and still no signal at maf.

i opened up the power fc to double check and i didnt see anything unusual.

can someone tell me what i fried and what to do next?

im hoping there is a relay or fuse i can check. i checked many but dont know where to look.

i searched for hours and found nothing on this specific problem.

thanks guys

Om1kron
03-07-2011, 04:34 AM
On the harness connector that goes into the ecu, for some reason my maf signal wire backed out when tightening it to the ecu and I had to take a jewelry screw driver and push it back into place.

I would start by looking there. If possible I would also make sure that you have continuity between all three items at the plug end and ecu end.

4795047

omg I actually posted something helpful. #WINNING

oh yeah I also forgot, it's VERY FUCKING IMPORTANT.

make sure the screw on the ECU is not in test or code modes otherwise you will have the problem you're describing. This happened to Nieko and he couldn't figure out for the life of him wtf was wrong lol.

Vatche
03-07-2011, 03:07 PM
cool thanks for the post.

i have to troubleshoot why im not getting any signal, and this gave me a few ideas,

the only idea i had myself was to check it at the ecu.

any other info would be great

airhead
03-07-2011, 03:27 PM
dude sounds like the same problem i had yesterday!
i was in the process of upgrading my SR as well
550cc injectors,z32 maf, tuned R.S ECU

there was two small cuts slipts in the MAF wiring due to a shitty wiring harness:( (ground and the 12v)
when i put the key to ON i smelt wires burning and smoke came out of my ECU.
ahh i fried my ECU

So after the ECU being fried i turned off the car removed the battery and inspected the ECU nothing seemed burned at all, so i put everything back. I started my car once again to see if the car will start up right, the car was just miss-firing and stumbling and smoke coming from the back of the exhaust. I checked and disconnected my injectors one by one just like how you did but nothing seemed to change.

shit happens! oh well. I have a new Wiring specialties wiring harness and I need to order a new tuned ECU.

i just end up putting all my stock stuff back on and everything worked fine.
GL hope that helps!

Vatche
03-07-2011, 11:26 PM
i got my car running today also.

the problem with the maf i never figured out exactly, but when i connected the maf and tried checking signal again, after removing the power fc and putting my stock ecu then back to power fc. when i put the power fc back in i still had no signal. until i plugged in the maf... which im guessing creates a current of some kind and i had signal... no clue but whatever it was originally i had soldered the wires backwards.

so after i fixed the maf i started the car and the idle was shitty and throttle response was 1-2 seconds lagged. so i changed the throttle body(including tps) to my old one which i knew worked.

problem solved. car runs great like normal.

thanks everyone