I was getting pulsing to my injectors, but they were not working properly. Testing with a noid light, they were firing.

Well, I went to a junk yard today, and ripped a ECM out of a 1990 corsica (same computer). I put my IROC chip into the corsica ECM, and started cranking.. Well, about every 40 flashes on the noid light, I get a very bright one. I'm guessing the very bright one should be what it always is.. I was not getting that bright pulse out of my IROC ecm.

Should I just order a new chip?

 

Well, if you had put this in the other thread it would have helped. Tossing up a slew of threads is rather annoying.

That said, it's not the chip that drives the injectors it is the injector drivers in the ecm itself. Test the power side of the injector harness and see what you get for a reading. Then check your fuses and make SURE your ecm ground is really, really good,

 

I don't get it. If the noid light was working why would you think the ECM/ Chip was defective? If you get a light that means the injector is getting a signal from the ECM. Perhaps bad injectors? What is the car doing that makes you think you even have a problem?

 

OK, I just read one of your other posts. If you have an 89 TPI set up it should have a Mass Air Sensor, you claim you have an ecm from a 91 TPI which is Speed Density. The ECM is completely incompatible with your setup.

Find a 165 ecm from a 1989 MAF TPI vehicle only, definately NOT from a POS Corsica!! I imagine the pins would be configured differently even if it were the same ECM.

 

What do you mean not from a POS corsica? They are ABSOLUTELY IDENTICAL in every single possible way except for the sticker on it. The prom is what seperates where they can be used.

And a 89 TPI CAN BE CONFIGURED to a speed density. Not only that, but this thing ran absolutely perfect two years ago, as my post stated.

I run a very large vbulletin 4x4 site, and I constantly see bad information being giving to users who are just looking for some help. Sometimes NO information is better then your bad information as you just posted.

 

Duplcate post removed. sorry

 

Different brightness in the firing. When I first hooked up the noid light, (my first time using one) I was getting flashing, repeat, and all of the same brightness.

With the new ECM, I am getting good pulses, but every once in awhile a VERY bright one... Since I do not have an alternator hooked up, I cannot be increasing voltage during a crank cycle.. If anything, I would be losing voltage. So if the ground outs for the fuel injectors in the ECM are pure and repetative, you would think that the pulse brightness would be the same.

 

I don't recall you stating your vehicle or ECM has been modified in any way to accept each other. You suggest you have a bad ecm or prom, my suggestion is more than logical.

If your getting a noid but "absolutely" no fuel into the cylinders you have faulty injectors, a bad pump or a serious fuel leak or blockage (filter.) Plain and simple. Is the pump turning on? Do you have fuel and pressure at the rail, is your system holding the pressure? I wouldn't worry about the change of noid brightness, length of voltage varies because of the ECM- BPW etc. If you insist check all grounds as previously stated and check the actual voltage on each connector. I trust a fluke 1,000x more than a $5 light bulb.

I'm making suggestions to help, take them or leave them its your vehicle. If you run a very large 4x4 site then you should post this and your coy remarks there.