[motcher41]

Had this car for two year now. Two winter seasons. Only when it's cold outside like right now 6°F I get a random misfire. Doesn't matter if I let it warm up, plug it in, don't warm up, run it to warm. Just will randomly pop up before it gets to temp. I tried to track it down last winter but no success. Uses no fluids. Replaced plugs, wires, coil pack, pcv valve, air filter. Cleaned maf sensor, iac, connectors.
Never throws any other codes.
Thoughts?

 

[Automender12345]

Could be some bad intake manifold gaskets. Cold weather the air is denser and would lean out your mixture. I had misfire at start up and it was an upper gasket. Since it is a random misfire by what you said what code. A random misfire code??? Need the code. Could be a bad PCV valve sticking open in cold. My one is heated to prevent freezing. Do you know the short term fuel trims at idle. Does it ever go away once it warms up.

 

[motcher41]

If I reset the code it doesn't come back until it gets cold. It was a p0300. Replaced PCV Valve. Sprayed around intake gaskets and not change in rpms.
It runs and idles very well

 

[motcher41]

Short term trims while warming up from cold start at idle around -1

 

[rsteve56]

What brand, number of plug and what gap?

 

[rsteve56]

What engine? What brand, number of plug and what gap?

 

[motcher41]

Vulcan engine. Autolite APP104 gapped to spec. .044 I think. Don't recall for sure but to spec.

 

[rsteve56]

The plugs sound correct. These engines rely on a good coil, I have tried aftermarket coils with bad results. The best choice is Motorcraft DG-532.

 

[motcher41]

Yeah I probably should have went with the motor craft coil. Got a Spectra unit

 

[Jeff K]

Yup, use ONLY the Motorcraft or BWD (Borg Warner) coil pack. All others are cheap junk, often bad out of the box. .

 

[87wagon320k]

The cap and rotor wear on these pretty quick once you go aftermarket on the Vulcans. That may be something to look at. I had a no start condition and it ended up being the distributor. Well, whatever the electronics in the distributor were called. Got one from the junkyard for $14 on a sale day. Lucked out that it was one someone through at the car before junking it. Score. Needed it, recession days. The rotor didn't fit tight so we used a guitar string bent around the shaft to make the rotor fit tight. worked for 30k miles until the trans went.

 

[jag1959]

The cap and rotor wear on these pretty quick once you go aftermarket on the Vulcans. That may be something to look at. I had a no start condition and it ended up being the distributor. Well, whatever the electronics in the distributor were called. Got one from the junkyard for $14 on a sale day. Lucked out that it was one someone through at the car before junking it. Score. Needed it, recession days. The rotor didn't fit tight so we used a guitar string bent around the shaft to make the rotor fit tight. worked for 30k miles until the trans went.

The car is an '05, no cap or rotor, lol. Next time you are trying to get to certain post threshold on a site maybe post bomb a bit less and read a bit more

 

[motcher41]

The cap and rotor wear on these pretty quick once you go aftermarket on the Vulcans. That may be something to look at. I had a no start condition and it ended up being the distributor. Well, whatever the electronics in the distributor were called. Got one from the junkyard for $14 on a sale day. Lucked out that it was one someone through at the car before junking it. Score. Needed it, recession days. The rotor didn't fit tight so we used a guitar string bent around the shaft to make the rotor fit tight. worked for 30k miles until the trans went.

Is there a way to thumbs down a post? LOL

 

[jag1959]

Is there a way to thumbs down a post? LOL

No but in this instance perhaps there should be...

 

[soundu]

i would look closely at all vacuum hoses for cracks and replace any that
look suspicious. Check PVC valve and the rubber that holds it for leaks.
The EGR could also be leaking. I would take the plenum apart and
clean out the throttle body for good measure if its full of the usual crud.

and, i would take all under hood ground lug connections apart, clean
as needed and retorque them down

bob

 

[Naughty Nate]

^^Yeah it might very well be a sticking EGR