NUMCHUCK

Ok here goes... I have a no start condition... I have 60 PSI of fuel pressure...No fuel is getting to the combustion chamber.... I replaced the spyder injector...I have 12 volts going to the red wire of the injector harness...and when plugged in I have 12 volts to the blue wire of the injector harness...What I am wondering is...Besides the PCM what controls the injector to open and close a signal to the injector to fire it?
Is the a crank shaft sensor or something? I have been fighting this problem for a few weeks...Any help would be great! Thanks

boatbuster

Before changing a whole bunch of parts, you should get the vehicle plugged into a ocbII reader to see if you have any codes showing up. Sensors and parts can get expensive.

Scrapper

he's right take it to autozone or advanced let them plug it in...cps is for the timing.....

dewaynep

Guys, it's a '93, No obdII. The 'Zone won't be able to scan it, they only scan obdII, not obdI. Can you verify that it starts with starting fluid? Do you have a noid light you can hook up to see if the injector is indeed getting a pulse from the ecm?

Scrapper

i still say it's the fuel pump is your problem.have you changed your fuel filter???? because if injecters it should back fire or not start at all if injecters..ok if you can keep it running with starting fluid..it is the pump..




SCRAPPER.....

NUMCHUCK

...I used a jummper wire and checked for codes...No codes...I did change the fuel filter....I replaced the fuel pump as well...It does start with carb cleaner.... I check the wires to the ECU from the injector harness...(with the computer unplugged) the wires do have continuty.... I tried to used a noid light on the injector harness...It didn't flash at all..But I do have 12 volts at the connector...Doesnt a noid light only work if one side is a ground?..with the injector harness plugged into the injector both wires have 12 volts. I have no idea what it could be besides a computer....

dewaynep

I have no idea what it could be besides a computer....

That would be my guess..... provided you do get spark and it will run momentarily on starter fluid or gas poured directly into the TB.

NUMCHUCK

Yeah...My boss is a tightwad...He got me a used computer from a wreaking yard...I am just wondering if its not another bad computer....
I do have spark like crazy....The last guy replaced all the ignition parts!

I was just wondering what tells the computer when to send a pulse to the injector....I would think if it was a sensor it would shoot out a code...I have no clue at this point!

dewaynep

I'm not an expert, there are real experts here though, but the same sensors that would tell the injectors to fire would also be used to fire the spark plugs. So, if you have spark, but no fuel then the sensors should be fine. One other possibility is the injector assembly itself is internally shorted and is frying the ECM. You may want to double check the injector assembly for shorts to ground.

NUMCHUCK

Well I pulled the upper intake back off...Checked the connector...nothing is shorting out....I am limited to a Haynes manual and my own knowledge....I was starting to think I was missing something...I guess I should get him to buy a brand new computer...

NUMCHUCK

I did replace the injector before putting in the used computer

ericn1300

check your crankshaft position sensor, no signal to the ECM = no fuel to the engine.

MT-2500

You should be getting a injector pulse on these two wires.
If 12 volts on both it is losing ground some place but remember the pcm pulses the ground side of injector to trigger injector.
Get a injector noid light and see if the ground side injector wire is pulsing ground.
To check for ground pulse hook one side of noid/test light to positive battery 12 volts and if it lights up or pluses it is getting a good ground pulse.
One place to check for bad grounds is on the thermostat housing mounting bolts.

__________________
Remember proper testing gives us the answer to many problems.
MT

NUMCHUCK

It doesnt have a crankshaft sensor...They did'nt put those on untill 96

JD483

Go bother the folks at Astosafari.com