88 Iroc Z L98 Auto. Car just died one day driving and it just cranked and cranked after that. Fuel pump primes, fuel pump relay good. Had weak spark, replaced ignition coil, ignition module, pickup coil. Has strong spark now. But it still cranks. Injectors are 16.1/16.2 ohms each but are not pulsing. Can the distributor itself disable injectors? I've noticed under the rotor there is a gear held down with rivets that is very rusty. Is this the magnetic pickup that sends a reference pulse or something?

 

check the fuse for the injectors.

 

Fuses are good.

 

under the rotor if it has 8 wedge shaped triangular looking teeth then yes that is the magnetic pick up, send a signal to the ECM, the ECM uses that signal to fire the injectors, on a purple wire (with a white stripe IIRC) I had a break in that wire and my car cranked and wouldn't start. Obviously not a common problem.

VATS will also cause your injectors not to fire.

 

It sends a signal to the ECM through the pickup coil or??? Because I replaced the pickup coil...the teeth in the distributor is part of the distributor, it's connected to the shaft that spins...how does this send a signal? Mines all rusty too. I have spark and fuel...is there a ESC or something as well on my car?

 

not directly, the p/u coil is connected to the ignition module which in turn uses that signal to time the spark and injectors.
If you have spark then I would think there is nothing wrong with the p/u coil.

It is possible that your new ignition module is defective, wouldn't be the first time.

 

Yea I meant to include that, I was interrupted in typing that post. The (HEI) Control module in the disributor turns the analong signal do a digital on/off signal. The module fires the coil and sends a cam reference signal to the ECM.

 

Does the distributor itself play a role in firing the injectors? The magnetic thingy is the pickup coil or is there another magnetic thingy? Also, is there a ESC on my car?

 

The pick up coil is deep down inside the distributor, you have to take the distributor apart to change it.
The ring with the 8 triangles on is called a, i think, reluctor ring, this is what creates the magnetic signal as the distributor spins.
All these components have to work together, if not your car wont start.
It will be much easier for you to install a reman distributor than just throwing parts at the old one. It will come with all new parts and a warranty.

Your car does have an esc, it's a square black box looking thingie mounted on the firewall near the fuel pump and maf sensor relays.

 

The only part the actual distributor that plays a role is the magnetic pick up, think of it as a cam sensor. The ECM actually grounds the injectors, but it uses the signal from the module in the distributor for a signal know when to do so.

You should have a 4 or 5 pin spark control module on the fire wall near the distributor on the driver side I believe. If you have spark then the module should be good.

 

I REPLACED the pickup coil. I DO have spark. It has fuel as well. The magnetic pickup is different than the pickup coil right???? And the ESC is working cause I have spark correct? In the picture, the gear with the shiny rivets that's part of the distributor...cannnot be replaced seperatly...that sends a signal????

 

Magnetic pick up and pick up coil in this reference are meaning the same thing. Yes what you have pictured is it. I honestly don't see it being rusty causing a problem. The electronic module that has 2 connectors that plug into the outside of it (2wire and a 4 wire) is what sends the signal to the ECM. What you have pictured is what generates the pulse that goes to the module in the distributor cap. There are two wires that come off the pick up that plug into the two bare tabs that stick out the back side of the module pointing into the distributor.

 

So, what else can cause no injector pulse? Fuses are good. Grounds are good.

 

Vats is a big one.

Bad ECM.

As I mentioned earlier I would check the continuity of the purple wire to the ECM. There was a break in that wire on my 91, it would crank all day and not start because the ECM wasn't pulsing the injectors. Fixed that wire, fired right up!

What grounds are you checking? The ones going to the ECM from the injector? Pink/Black is 12v+, Green and Blue are the grounds they go to the ECM.

Page 8 has the fuel injector wiring circut on it.
http://www.fastgm.com/wiring/91CamaroWiring1of6.pdf

 

I don't have vats. I checked the injector grounds behind the heads. All the wires to the ECM look good. Should I change my distributor?

 

If you have spark I would not change the distributor.

 

But it also tells the injectors to fire no?

 

i have had that problem 2 times...1st time was the vats,i had to splice in some resistors to manipulate the theft system..2nd time i had cleared the codes with disconnecting the pig tail wire by the battery that powers the computor and didnt plug it back in good and ran off the road..car died wouldnt start..checked that wire and it had come undone

 

Oil pressue switch? I believe you have to have a minimum amount of oil pressure for the fuel pump to operate. Maybe the wire came off?

 

Yes, but it is my understanding module does both, or nothing. So it wouldn't fire the coil and not send a reference signal to the ECM or vice versa. You can pull that module and have it tested at autozone to rule it out. They have a wells machine, I personally tested my module there.

 

I'm really getting confused. I have spark and fuel. It cranks but will not catch. It doesn't even try to catch, just a strong crank. The pickup coil is new and so is the ignition module and coil. Everything else is in alright shape. The "Another won't start" thread had a guy who had everything going strong like me, he changed the distributor and it fired up and no problems since. I replaced the pickup coil in the distributor but it still won't start. If the pickup coil is the magnetic pickup, then what other problem could I have?

 

Car is running folks! The timing was way off. All who have spark problems and the like should check the condition of the pickup coil or replace it if you haven't done so already.