1jz over fueling
 

my 1jz is over fueling realy bad it wont pass 3000rpm i have tried fuel pump,injectors,coil packs,map sensor,intercooler,ecu,and every sensor and unit that is in the engine bay . can anyone please help

when you say over fueling do you mean running rich?
do you get backfires things like that?
First lets start by checking what codes you have.
off the top of my head.. Fuel pressure regulator?
TPS, MAF, ECT, and then O2. The O2 sensor is the last on this list

post back with codes. oh snap you said Ijz. bummer I've never owned one.
Perhaps someone else can chime in.

ya running rich and backfiring at not giving any codes everything is coming up ok

hows your timing?

You probably have leaking capacitors in your ecu. I kno you said u tried other but 95% of 1j ecu have leaking capacitors I had to replace mine not even a week ago.

The good thing is that it is easy to do if u kno how to solder. And about $2 for parts. Here is a link.

http://www.toymods.org.au/forums/sho...placement-info

Knock is another possibility.

i have tried a ecu i know is working perfect and its stil the same

tried that to is there any relays or units inside the car that can cause this

No.

You could always get a piggy back system and an a/f gauge. The 1j runs rich from the factory.

A dirty airfilter can also cause it!

Check your spark plugs. gapped between .020 to .028 all 1j are really picky when it comes to spark plug gap. mine has to be set at .024 EXACTLY or it will putter.

No, extra rich fuel and reduction in timing is a function of the ECU in the presence of ping and knock. If you have changed the octane of the fuel you're using and the climate hasn't changed significantly a ping could be bad news; If it's gotten hotter and/or drier and you aren't using a high octane fuel you may want to try it and see if performance improves.

How did you test the MAP sensor and the IAT sensor?