I have replaced everything and still no fire/spark.

Check the crankshaft position sensor

Check and test the distributor pick-up coil

On these it best to replace the pick up coil and main ignition coil make sure you have the ground strap inside the coil housing or you can get a rebuilt distributor. Here are the instructions in the diagrams below to help you fix the problem:

Procedure
1. Disconnect ignition switch battery feed wire and tachometer lead (if equipped) from distributor cap. Also release the coil connectors from the cap. (Do not use a screwdriver or tool to release the locking tabs.)
2. Remove distributor cap by turning four latches counterclockwise. Move cap out of the way.
3. Disconnect 4 terminal ECM harness from distributor.
4. If necessary remove secondary wires from cap, release wiring harness latches and remove wiring harness retainer. The spark plug wire numbers are indicated on the retainer.
5. Remove distributor clamp screw and hold-down clamp.
6. Note position of rotor, then pull distributor up until rotor just stops turning counterclockwise and again note position of rotor.

To insure correct timing of the distributor, the distributor must be installed with the rotor correctly positioned as noted.
If the engine was accidentally cranked after the distributor was removed, the following procedure can be used for installing:

a. Remove No.1 spark plug.

B. Place finger over No. 1 spark plug hole and crank engine slowly until compression is felt.

C. Align timing mark on pulley to "0" on engine timing indicator.

D. Turn rotor to point between No. 1 and No. 8 spark plug towers on distributor cap on 5.0L engines, between No. 1 and No. 6 on 3.0L and 3.8L between No. 1 and No. 2 on 2.8L and between No. 1 and No. 3 on 1.8L, 2.0L and 2.5L engines.

E. Install distributor and connect ignition feed wire.

F. Install distributor cap and spark plug wires.

G. Check engine timing.

Use AC Delco parts for best results. Check out the diagrams (below). Please let us know what happens.

Hi,

There was a technical service bulletin years ago that indicated problems with the ignition coil breaking down. Here is what it says:

" General Motors has determined certain 1984-1985 Chevrolet Camaro and Monte Carlo models with 5.0L V8 engine and 1984-1985 Chevrolet Corvette models with 5.7L V8 engine may exhibit declining ignition voltage of the high output ignition coil.

High ignition coil temperatures combined with the stress of higher voltage may break down the epoxy coating of the high output ignition coil secondary windings. Declining ignition voltage may lead to engine misfire, hesitation, sags, or no re-start. Correction will consist of replacing the high output ignition coil and module."

I have a feeling this is the issue. If there is no spark detected, the PCM will turn off the fuel pump.

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Here are directions for testing the coil. I believe this has an integral coil in the distributor. If I'm wrong and it is in a remote location, let me know. The attached pics correlate with the directions. The directions also include checking the pick up coil.

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1985 Chevrolet Corvette V8-350 5.7L
Units With Integral Coil
Vehicle Powertrain Management Ignition System Distributor Testing and Inspection Component Tests and General Diagnostics Units With Integral Coil
UNITS WITH INTEGRAL COIL
Fig. 15 Testing integral ignition coil

Pic 1

Ignition Coil Testing
1. Connect a suitable ohmmeter as shown in Fig. 1, step 1. Using the low scale, read ohmmeter. Should be near zero or zero. If not, replace coil.
2. Connect ohmmeter both ways as shown in Fig. 1, step 2. Using the high scale, read ohmmeter. If both readings are infinite, replace coil.

Fig. 16 Testing integral coil distributor pickup coil

Pic 2

Pickup Coil Testing
1. Remove distributor rotor, then disconnect pickup coil leads from module.
2. Connect ohmmeter as shown in Fig. 2, step 1. Connect a suitable vacuum source to vacuum advance chamber (if equipped) and note ohmmeter reading throughout entire vacuum advance range. If no vacuum advance is used, flex leads by hand to check for opens. Ohmmeter should read infinite at all times. If not, pickup coil is defective and must be replaced.
3. Connect ohmmeter as shown in Fig. 2, step 2. Repeat step 2. Ohmmeter should read one steady value between 500-1500 ohms. If not, pickup coil is defective and must be replaced.

Note: Ohmmeter may deflect if vacuum advance range causes timing core teeth to align. This is not to be considered a defect.

Fig. 14 Testing Hall Effect switch

Pic 3

Hall Effect Switch Testing (If Equipped)
1. Carefully noting polarity, connect battery and suitable voltmeter as shown in Fig. 3.
2. Voltmeter should read less than 0.5 volts. If not, replace Hall Effect switch.
3. Insert knife blade as shown in Fig. 3. Voltmeter should read within 0.5 volts of battery voltage. If not, replace Hall Effect switch.

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Let me know if this helps and what you find.

Take care,
Joe

Find/Inspect/Test the crankshaft position sensor-also the voltage reference on the connector.

Resistance check close to 1kohms -its okay.

You have replaced coil/ICM/CPS dunno if it has a camshaft sensor-if it does check that too, if not could be coming from the computer

BTW did you check for the ref. Voltage at the connector on the CPS

Have checked for codes? What is "pancarditis"? Has fuel pressure been checked?

The knock sensor wont give you a no spark condition. It simply advances, or retards timing when it senses engine knock. What engine is in this car, the LS1 I believe right? If so, your distributor sits behind the waterpump, kinda sucks to change.

Just wondering if you have solved this issue yet?

Maybe faulty ignition module