2JZ injectors not injecting..what could it be?

**Mr Ed** · 01-04-2009, 01:57 AM

Stock 2JZ in an A70 Supra, stock injectors, stock ECU. Not much of the engine loom has been touched, only connections for battery, ignition, ground, starter, fuel pump, etc.

Engine was running before but I stripped down the plenum, fuel rail, injectors to have them cleaned up. Plenum was sand blasted, rails was just wiped down and injectors were professionally cleaned and flow tested. This was done about 2yrs or so ago...engine has not been running since.

Another problem was the fuel pump seized up and the tank was full of unidentified white crystals (coating the inside of the tank)...had a thread on it before and someone suggested it might be sugar in my tank. I fucking hope it wasnt and fucked if i know when it would have happened (car has been off the road for 5yrs but normally locked up), but the tank and pump have now been replaced.

The crystalised crap doesnt seem to be in the fuel lines or rail (it was VERY visable in the tank).

Everything back together now. Engine turns over, all cylinders have spark, the fuel rail has pressure, injectors have power but i dont have a way to test if they are pulsing (we tried a test light on the plug but i think the pulses are too quick for a tungsten glow to light up at all).......the engine wont fire.

We took the IC pipe off and sprayed some 'start ya bastard' into the throttle, cranked it...fires (but obviously wont run), so it must be a fuel problem.

We pulled the injectors out and theyre off to be tested tomorrow...but im not all that sure it will be them. We've also got another rail and regulator we're going to try as well.

I havent tested the crank/cam angle sensors or MAP sensor yet, as i didnt have a multimeter with me at the time, or know what the resistance range off the top of my head. Im pretty sure it wont be them though, as i tested them a while ago and they were fine and they havent been touched since.

Does anyone know if a stock 2JZ ecu will stop injecting fuel due to any errors? (ie. disconnected/munted sensor)

Any other idea WTF is up?

**oldcorollas** · 01-04-2009, 02:54 AM

injectors can gum up after 2 years.
they should make a clicking sound if the solenoid is moving.

btw, did you save any of the white crystals? easy to have them analysed if you know people with access to machines at a univ

(although sending thru the mail might arouse... suspicions....

)

**thechuckster** · 01-04-2009, 08:19 AM

wilbo and i found an MZ10 tank that had green/yellow fuzz growing inside it and the remnant fuel had some distinctly non-petrol odours... was very entertaining.

**Mr Ed** · 01-04-2009, 11:47 AM

Yeah still got the old tank, pump and pump bracket. Would be very interesting to see what they are, as from all my efforts I cannot find a solvent that will dissolve them.

Another bloke suggested i give the injectors a bit of a tap, maybe pulse full battery power through them a few times and then see how it goes.

**oldcorollas** · 01-04-2009, 12:33 PM

well, if it sugar it will dissolve in water.
if it was in the petrol, it will dissolve in petrol

maybe just oxides? are the insides of the tank zinc coated?

**Mr Ed** · 01-04-2009, 01:45 PM

There was pretty big chunky crystals in there, didnt look like any sort of oxidation Ive seen before.

To be honest....im not sure if i tried to dissolve them with hot water. Might have a look at that tonight.

**oldcorollas** · 01-04-2009, 02:44 PM

oh, are they high or low Z injectors?
if they are low Z adn you hit them with 12V directly, they may not be happy..
if you just drag the lead across to get occasional contact (think dragging jumper lead across something to get sparks) but just connect and hold is nto ideal (no fuel cooling and higher PW than usual for high Z and much higher current than usual for low Z)

and like bill said, they are basically just a coil with a nail in it that moves back and forth when power is applied

**Mr Ed** · 01-04-2009, 03:19 PM

Yeah high impedance...but i wont be holding constant power to them anyway. Just a quick tap.

**oldcorollas** · 01-04-2009, 03:34 PM

high impedance should be ok.. since they don't need resistor, and have a max of abotu 1amp..
tapping will be what frees it, rather than holding it on anyways..

**The Real Roadrunner** · 01-04-2009, 04:28 PM

id still get them flow tested anyway as it sounds like they corroded shut which may cause incorrect flow/ spray pattern

**Mr Ed** · 01-04-2009, 05:59 PM

Yeah frikin flow testing and cleaning costs a fair bit and they were done 0km ago...im out of work at the moment so if i can avoid extra costs I will be. As soon as I get some $ flow testing will be high on the priority list.

**The Real Roadrunner** · 01-04-2009, 10:14 PM

tell them to throw them in an ultrasonic bath and then flow test them, shouldn't be more than about $70, which is a shitload cheaper than a piston.

Maybe only done 0kms ago but id never do it and just leave them sitting around for 2yrs (they probly should have told you that)