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ThreeOhFive
08-20-2011, 04:59 AM
Tested fuel pressure only, 43 on prime, 43-45 cranking. Injectors held pressure for an hour until I disconnected the gauge. Replaced the fuel filter, ECM, plugs, will be putting a TPS and O2 in tomorrow, oil change and coolant flush. Adjusted the timing, it drove a little bit, but it runs like crap and still won't run with eight injectors plugged in. I have not ohm'd the injectors yet. Any idea's???

xpndbl3
08-20-2011, 05:15 AM
carb time ;)

2QuikTA
08-20-2011, 05:18 AM
Seriously....you need to get a bus pass

ThreeOhFive
08-20-2011, 05:22 AM
I've got a daily driver ya know...

No carb going on this car.

ThreeOhFive
08-20-2011, 05:38 AM
Will add a few more details, pulled the ECM today, the ECM it had in it was a "reconitioned" factory replacement, so it had been replaced before. The car also has good spark, the coil is fine. It is not throwing any SES codes at the moment.

xpndbl3
08-20-2011, 05:51 AM
carb > tpi


by LIGHT years

Wrencher
08-20-2011, 06:19 AM
What do you mean it wont run with all the injectors plugged in?
Do you have to disconnect some of them to get it to run?
OHM them out before anything else, if any are less than 12 ohm replace it.
Check them cold & hot....

Formula WS6
08-20-2011, 03:15 PM
key off and unplug every injector. one by one place the mulitmeter leads on each injector terminal, one injector at a time. put the mulitmeter on the ohm setting

anniversaryz28
08-20-2011, 04:06 PM
Does it matter which injector you unplug? Maybe one is hung open and just dumping fuel...i got your text the other day, i will respond shortly.

Thirdgen89gta
08-20-2011, 05:32 PM
What was the fuel pressure when idling? Under load?

I thought it ran sometimes.

If I thought 43psi at cranking was good enough I'd never have guessed my fuel pump was bad because it could do that no problem. It wasn't keeping up with demands at WOT. At WOT fuel pressure dropped to 23psi.

Now why did you go and replace the ECM? The ECM usually does not die.

Check your fuel pressure at idle and under load! 43psi at crank means nothing.

Wrencher
08-20-2011, 05:50 PM
How exactly do you ohm the injectors, key in the ignition, turned to acc, you unplug them each individually and then put the - tester on the plug in, and the + on the connector?
No do it just as Paul said;

key off and unplug every injector. one by one place the mulitmeter leads on each injector terminal, one injector at a time. put the mulitmeter on the ohm setting

ThreeOhFive
08-20-2011, 07:34 PM
It wasn't running when I tested the fuel pressure. It just started running again two days ago. It's not running again. ECM wasn't the problem, I replaced it because the symptoms it was having, some advice on TGO and all the mechanics around here said I needed to try that first. It ran today, but died on me going around the block, wouldn't restart, and I towed it back home. I have an ohm reader I can test everything today. Normally it's the eigth injector that has to be unplugged for it to run. How exactly do you ohm the injectors, key in the ignition, turned to acc, you unplug them each individually and then put the - tester on the plug in, and the + on the connector?

ThreeOhFive
08-21-2011, 01:19 PM
I ohm'd my injectors today. They were cold when I read them, but I think I have my answer to why my car runs like shit.

#1: 16.3
#2: 16.3
#3: 16.3
#4: 16.3
#5: 3.4
#6: 16.4
#7: 4.8
#8: 5.1

3 failed injectors!!!

Wrencher
08-21-2011, 02:19 PM
Yup that'll drive the circuit protection drivers for the injectors in the ECM nuts.
@ 14 volts the 16.3 ohm injectors will need 0.8589 amps to open. OK in spec for high impedance injectors.
@ 14 volt the 3.4 ohm injector alone will need 4.11765 amps to open.
So it tripled the amperage on that bank. TPI is a batch fire injection system, it fires 4 @ a time.
Once there is a low resistance injector the driver in the ECM can only supply so much current(amperage) & it will shut down to thermally protect itself.
That & the lowest resistance one in the bank is the path of least resistance so it will consume most of the amperage supplied during the injectors firing.
That is till the normal end of the event or the thermal shutdown of the driver.
Be glad it has the protection built in there are lots of MFG's who do not do this to this day.

quickslow
10-11-2011, 08:43 PM
Ya..

Make sure you keep in mind the 02 sensors and cats are clogged with black shit now maybe to.
I had a bad runner that cloged the cats. Car would warm up and the cat would warm expand
and shut the car down like a mystery. Disconnected right before cat as a few last effort test
after 2hr of misc testing. Bam ran like a champ again, so did a quick delete pipe and car was
solid again, ran like a champ.

Thirdgen89gta
10-11-2011, 08:51 PM
NM responded to a "quote".

Aaron have you replaced your injectors yet?