OK so I have the UIM off. How can I test injectors?

How do I test ohms on it,etc......

SO I understand right.
The injectors with key on shoudl have 12v going to them.

The ECU then uses a ground to initaite the opening injector?right?

Know what ins I should test on the ECU/interioir side of te harness?

 

boink

 

OK,

So I did a little searching.

Hailer has something about putting the keys in the on posistion and checking for 12v.

So far the harness is good.
Each injector had 11ish volts.

Next I'll check the grounds.

I sanded down the ring terminal so that's good.

I did notice a LOT of corrosion inside the injector plugs so I took a needle and scraped the inside then sprayed them with cleaner. Hopefully my rear rotor not running was something easy like this.

 

The primary injectors have Ohm resistance of 33. is that normal?or even matter?

How do I determine high impedance through electrical checking?

 

This would have been a lot easier just reading the whole system out from the ECU, but you're already there now, I guess (at the primaries). Be careful taking resistance readings back through the harness to the ECU, if the ECU plug (#3) is still connected. If you do (one meter lead on one of the injector connector pins, the other on the other pin), you should get something in the 9 kilo-ohm range, then it'll start falling, all the way to zero, due to the capacitive reactance in the ECU internal injector circuits...Make sure the meter has no more than a 9 volt power supply, if you do this...

 

Did you say you read 33 ohms through the injector only? That's strange...Is your meter zeroed properly at the resistance scale you're using?

 

ok well the injector ohms was a little weird.

So far i haven't gotten a consistant reading.

It's been all over from 1k ohms to 90k ohms.

 

and this is at the injector only, you're not reading through the harness at all?

 

yeah,
Just through the prings on the injectors.
They're sitting here next to me.

 

ALL of the injectors are reading 33 ohms? Are they stock? Stock ECU? You may have just found your prob

 

Normal OHMs from high impedence injectors are between 11-13 OHMs according to the FSM. Low Impedence injectors are around 2-3 Ohms.

33 Ohms is unheard of in a stock car, turbo or non-turbo, at least as far I know.

 

Yeh, the funny thing is, it's a simple coil of wire around a magnet, basically- they don't just up and "break" and go to some ungodly resistance level, if anything they'll fry and create an open...I gotta ask this, Digi, are you SURE you're using the meter right?

 

I'm using it right.
The damn meter is screwign up a bit.

The meter's lines had 60ohms so it was throwing me off.

I just tested it and it got 71 so deducting the lines resitance I get 11ohms through the injector

 

LOL, calibrating the test equipment to read what you want it to, I like that!, j/k...

OK, back to the harness, how'd it go?

 

I'll check ECU side tomorrow.

I'm really thinking it was those corroded injector terminals.

I need to know if there is a way of checking that the injectors even open.

Can I use a AA or doesit have to be a 12v source?
I'll just tap the prings to see if it clicks open.

 

Jesus... what kind of meter are you using??

 

take them out and send em to cruzinperformance, they charge 12 bucks an injector for cleaning calibrating, sanding, and painting, and they aupply new orings pintle caps, and grommets. www.cruzinperformance.com

 

He already did..

 

here are the stats for the injectors.

They are 3 and 4. 1 and 2 are 460's

 

You can use jumpers from your car battery if ya want- I've done it before with my "injector flow test" setup I've got...What do you think gives 'em juice in the first place? Just "click" 'em on & off a couple of times to satisfy your curiosity. Take note, I've had one that clicked fine, but was still clogged up with rust and wouldn't flow, but you just got 'em cleaned, so you won't have to worry about that. As far as proper polarity on the injectors when "zapping" them, I wouldn't think it would matter, but I figured out which pin was + from the wiring colors (The B/Y wires go to the positive pin, I think it was the left side pins (facing the injector), IIRC), and used the proper polarity...

After you get everything back together, check for your 12v on pins 3C,3E,3F, and 3H at the ECU (key on), and check the ECU pins to ground at 3A and 3G (power off)...If it's all good, then your harness is all good for the injectors...

 

well I didn't bother. like you said me testing them won't really prove anything.

So I put everything back together and got a fuel line psi gauge.

I'm charging the battery and then will give it a try.

Oh yeah and is 27-30psi at starting a good number?