Packard Forum Index » V-8 (1955-56)

Have a problem.

Car starts. Can Rev it. But in gear. Giving it gas no acceleration.

Don't know how pertronics module works. But can they give up under load.

Took carb off Christmas day. Put it back on . But started it today. Had to crank it awhile to get gas up

The only thing I think might of happened. Was some over load on module.

Even with all my diodes.. only other thing I have is the mid 60s. Delta capacitive discharge unit.

Never had a problem with it..


Thanks.

Assuming all cylinders quit when load is applied: A bad coil can do that, as could a dirty or damp coil. Or a bad rotor, or a bad coil wire. Low or incorrect ignition supply voltage could cause it. A bad ballast resistor could cause it

Moisture in the distributor could cause it.

A fuel delivery issue could cause it.

I am curious why only in gear. It would seem that if you can start and rev the engine the module is putting out a spark so must be working. Are you thinking the spark is disappearing or breaking down is the reason for no acceleration or does the engine exhibit fuel starvation symptoms so could it be low gas delivery before the carb. The no acceleration sounds very much like an issue I had when a fuel filter clogged on the 56 or when the bore in the flex hose between the fuel pump and fuel line internally collapsed on a 54. Both cars would get enough gas to start and idle just fine and even rev up to a certain rpm with the gas supply they were getting but any farther or any load would need more fuel which could not pass so they fuel starved and engines stalled.

Thanks guys.

That's what I don't get. Why in gear.

It was running fine. Before I took carb off. But the automatic choke was hanging up.

So fixed that

Not much on pertronics questions.

It does say. If you keep key in on position. . Not running.

The module can fry. I did email them.

It does feel like gas issue. But. Since I can Rev it. And it idles fine.

The battery was on high charge when it started. That's why I was thinking module..

Ignition can fail when the engine is loaded, and yet still perform OK under light load, idle, and even starting.

Of course, lack of fuel can present similar symptoms.

Another possibility is that you have a wiring issue that could come into play when the engine is placed under load, which causes the engine to shift slightly on its mounts. The slight movement of the engine could cause a poor connection to open or a chaffed wire to ground out. This would probably affect wiring under the hood and on or near the engine.


Poor fuel delivery might show up if you put the car in neutral and brought the engine up to about 2,000 RPM and held it there for half a minute or so. The increased fuel demand might cause the engine to slow down or die if fuel delivery is very poor.

******A bad accelerator pump can cause an engine to stall when attempting to accelerate IN GEAR FROM A STOP, especially when the engine is cold. This is usually more noticeable with an automatic transmission.****

Thanks TX

My first attack is to take the cd out of the system.

Did talk with pertronics tech.. his thoughts also. If it's starting. Module is ok.. but sent troubleshooting info too.

He also said. Ground . That's mainly the complaint ..

Pertronics has had it with ca.

Moving to KC.

Got around to un doing the delta cd.

Pertronics only. With a diode before + on coil both wires. Packard and Pertronics

I have power on take off..

Uneven on power so carb is either cold. Or other problem..

So Pertronics is ok.

Delta cd pooped out after 60 years.

Before I venture into Edlebrock. What are your guys options.
On the Buick or Cad 4gc. Not sure where the vacuum port is on them. But only thing I see is the excel pump is smaller.
Maybe the manifold is different.