[68Phoenix]

Last week, for no apparent reason, when I started my car it immediately began to misfire badly. The car will barely idle. The misfire continued after the engine warmed up. I don't want to change anything without asking the experts. What is the first thing you should check?

The winter was COLD! So I suspected the fuel pump, but it's not leaking. I pulled the fuel filter and it was filthy! But a new fuel filter didn't change anything. The engine will rev-up without hesitation, but I can still hear a misfire at 3000 RPM. I had used and started the car several times over the winter, and the last time I drove it the car was running great. Could the gasoline have suddenly gone bad?

One clue is removing the brake booster vacuum line... connected directly to the manifold, caused the engine to speed up a lot and seemed to smooth it out some also. It's like my engine can't breathe. My instincts say the fuel filter didn't keep everything out of my carb, which now needs rebuilding.

Advice needed!!! I'm going out to check the vacuum advance can since it just occurred to me that's another diaphragm that will crack in cold weather.

 

[68Phoenix]

Vacuum advance is fine. But, I'm not reading any vacuum from the ported line on the carb... at any RPM.

 

[MrBill66Malibu]

What kind of ignition system? If it's a points dist sounds like a bad condenser.

 

[zombie1969]

Remove the plug wires one at a time trying not to get zapped until you find the one or ones that don't seem to make it run worse or make very little difference then at least you will know what cylinders to start looking at for a problem.I always use a test light because its quick and you don't get fried.The clamp end goes to ground and I stab into the top of each wire boot coming out the dizy till I find the dead cylinder/s.

 

[Dave427]

By giving your engine the huge vacuum leak by pulling the booster hose off, tells me it is flooding.
Look down the carb to see if it is dripping while idling.

Dave

 

[68Phoenix]

Electronic ignition. Need to buy a new timing light. Carb looks very wet. Will go buy inductive timing light and check spark. Spark, Fuel, Air... right?

 

[Jerry Briggs]

Pull the distributor cap and see if the contacts and rotor button are corroded. Sometimes will happen in storage or in damp weather.

 

[68Phoenix]

Pull the distributor cap and see if the contacts and rotor button are corroded. Sometimes will happen in storage or in damp weather.

The contacts did look a little corroded, but if I can ask a stupid question (I didn't install this ACCEL system): I do have a condenser inside the distributor cap, next to the ECM. Could that be it? MrBill66Malibu is right, this is acting like a bad condenser.

Wow... is there like a global shortage of induction timing lights with advance? The last time I looked at them they were ~$70 now >$100 for the cheapo ones. Gotta check online.

 

[68Phoenix]

I just wanted to post back. For the 2nd or third time with my car, i found a broken piece of the component that was never removed. My distributor had a piece of an old distributor cap hidden under the vacuum advance centrifugal weights. Shown below. I am replacing the ICM and the capacitor/condensor just to be sure, but I can see wear spots on the advance centrifugal weights suggesting this chunk of plastic was probably causing the sudden problems.

 

[zombie1969]

That dizzy has seen better days why not get a new one there cheep enough.Not saying its gonna fix anything but people always do tune ups replacing everything and don't give a thought about the dizzy.

 

[68Phoenix]

That dizzy has seen better days why not get a new one there cheep enough.Not saying its gonna fix anything but people always do tune ups replacing everything and don't give a thought about the dizzy.

Might be a good idea (although I haven't changed a distributor since I was about 18 yrs old). Before I do, can anyone tell what this orange-colored stuff is visible through the gap in the distributor base? (I know the weights are out of whack in this picture)

 

[Ark68SS]

That's the insulation for your pickup coil. It looks pretty crappy. I'd say it's time for a new distributor instead of trying to make a silk purse from a sow's ear.
BillL

 

[68Phoenix]

That's the insulation for your pickup coil. It looks pretty crappy. I'd say it's time for a new distributor instead of trying to make a silk purse from a sow's ear.
BillL

Bill, this is my entire car you're talking about :yes: