No injector pulse - Stumped

[Jerryl]

Back from my nap. . . . . . . . . . 1984 HA GN - Car has been running well, suddenly stalled on the road, and went in “no start”. Turns over fine, but oes not catch. With some carb cleaner, it catches and starts. The following has been verified;
Car has no injector pulse , spark=OK, no codes, FP runs, FP good, SES light on with key on.

• Tried limp mode, still no start.
• Injector fuse verified good, voltage at injector - Noid light does not blink when cranking.
• Type 1 – 87 Delco Module/coil <500 miles, Casper HW, conversion harness, ign module plug is new and tight, has Caspers conversion plug.
• Cam sensor voltage to “plug ground” (main harness) is ~10.5V
• TPS 0.42V scanmaster.
• http://www.vortexbuicks-etc.com/no_start_tree.htm - Changed ECM & chip - Page 2 - step 8 -– No pulse.
• http://www.vortexbuicks-etc.com/no_start_tree.htm - Page 2 - step 9 – No blinkie.
• Replaced cam sensor cap, interrupter ring is tight.
• Module pins P & N have power with key on, and during cranking.
• Replaced crank sensor – Had slight damage.
• RPM in dash flashes when cranking

Questions;
The car has spark, so it points to the cam sensor, but the noid light does not blink when performing Page 2 - step 9.
Any ideas?

 

[TurboBob]

you need both a good cam and crank sensor to get spark. since it runs on carb cleaner, the cam and crank sensors would seem to be
ok as far as the ignition module is concerned.

the cam and crank sensor signals are buffered by the ignition module on their way to the ECM.

my guess is the crank signal is not getting to the ECM (from the ignition module) or a bad ECM.

B

 

[Jerryl]

you need both a good cam and crank sensor to get spark. since it runs on carb cleaner, the cam and crank sensors would seem to be
ok as far as the ignition module is concerned.

the cam and crank sensor signals are buffered by the ignition module on their way to the ECM.

my guess is the crank signal is not getting to the ECM (from the ignition module) or a bad ECM.

B

Thanks Bob.
I had already replaced the ECM . . . . Going to put a scope on the cam and crank sensor.

 

[S10xGN]

Possible wiring (harness) damage including loose pins?

 

[charlief1]

HE'S ALIVE!!!!

Glad to see you on again Jerryl. When you say it starts do you means it runs after it starts or just starts?

 

[Jerryl]

Possible wiring (harness) damage including loose pins?

HE'S ALIVE!!!!
Glad to see you on again Jerryl. When you say it starts do you means it runs after it starts or just starts?

The motor turns over just fine, but did not start at all unless you sprayed carb cleaner in the in the TB.
Had my buddy come over to assist and we found the problem to be a broken wire, about 5 inches from the ECM, on B5 – Ref Pulse in.
Thanks for replying gentlemen.

 

[dr_frankenstein]

Nice to see ya again Jerry!

 

[Jerryl]

Ok, I have additional questions;
Car starts up fine and idles fine, no codes, no hick-ups.
One thing we noticed on the scope is the missing wave on the cam sensor (A11). It is actually a flat signal.

Does this mean the module is bad or could it be something else?