Cold weather drivability

Problem: I have a 232 that runs like a Swiss watch in summer, but HATES winter like no other.

I've studied the heck out of it and one problem is the exhaust manifold warms up fast and releases the choke quickly, but the intake manifold stays cold. The result is a super lean engine that runs very rough and is down on power.

On top of that, the engine coolant temp gradually rises enough for the CTO to bring the EGR into operation even though the engine is still running way lean due to a cold intake manifold. Now it runs even worse.

AND...the coolant temp rises very slowly. I mean my 360 and 4.0L warm up twice as fast as this engine. I have to drive 10 miles for this engine to hit 170*. What the heck?

Even after the engine has run for several hours straight and is up to 195*, the intake is still too cold to run right.

I have put in several new 195* thermostats, the stock warm air intake on the air cleaner works as it should, the heat damper works as it should and I have even wired it CLOSED with no luck. Everything on this engine is as it came from the factory. I have blueprinted the carburetor and every emission control. I have set the ignition timing, timing advance, idle speed, fast idle, everything to the book. Yes, I have even tried retuning it off specification with no luck.

Like I said, this is on 10-40* days. On a 70-110* day it is the sweetest motor in the world. What the heck?

I can mask the issues by forcing the choke to stay nearly fully closed all the time and disabling the EGR...but those are not real solutions. I cannot run around with a glued shut choke. That is not right.

I cannot for the life of me figure out why this engine hates the cold so much when I have done literally EVERYTHING to it short of leave the choke on all the time.

I cannot believe they ran like this through Kenosha winters, which are FAR worse than my Kansas ones. What is going on here?









Edited by FSJunkie - Aug/12/2014 at 1:16am

Would it be possible to convert the automatic choke to manual using a cable?

If you have power brakes, make sure the booster isn't leaking vacuum.The wrong PCV will flow too much air and lean it out too. Alcohol in modern fuel makes older motors run different now. Have you done a water trickle flush to clean the valves? Timing chain slop is a big issue too.
   I spoke with Echlin about 10 years ago about the ignition coil and how running my points with the IC12 they sell made it run much better without the every 6 month points replacement the one they listed caused. (I think it was IC13) That is what they now list for most domestic points vehicles. It's actually an electronic ignition coil with double the potential output of the points coils.


Edited by carnuck - Aug/12/2014 at 12:15pm

Thick oil causes the cam to turn slow so all the chain slack retards the cam until the oil warms up.

Fluffy73 wrote: Is your car still using the manifold heat tube choke? I've cured a lot of issues on my sixes by converting to an electric choke. I've also driven mine in the bitter of winter with no issues. Secondly, do you have the warm air tube connected to the manifold heat stove?  That may aid the warm up period if it's not. Thirdly, (and I may be wrong on this one), I thought EGR was only supposed to come into play under a running/light load situation - not at idle or WOT. Try disabling your EGR next cold day to see if the problem goes away. If it does, you've narrowed the problem down.

Still has the hot air choke. Electric chokes in my experience open up FASTER than hot air.

Yep, warm air intake on the air cleaner is operating and hooked up as it should. That was pretty much the first thing I checked.


EGR only operates when the engine is above 115* coolant temp and at light to moderate load at part throttle, so no, I do not notice it at idle, but as soon as I give it gas and get up to ~3 MPH I sure notice it! Talk about a bog... But it's perfectly happy taking EGR in summer. Just in winter on top of idling like crap and being down on overall power, it can't take EGR.

Whatever it is, I'm sure to find it this spring when I rebuild the engine, I'd just like to find it sooner.