1978 4 Cyl Hard to Stay Running.


Dec 5, 2009
Hey guys,

I've only got about a week left to figure out this problem, so all help is appreciated!

I have 78 Coupe - 4 cylinder - 4 speed.

I'm having issues keeping it running at cold start. Once it warms up it's fine.

If my foot isn't on the accelerator, the car will instantly drop rpm until it stalls out, struggling to stay running until it finally dies.

Like I said, once it warms up, it idles between 1200 and 1500 rpm.

Any idea's of where to look for a gremlin?

Thanks guys!

- Brandon
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I would say hte easiest fix is to keep your foot on the accelerator. After all this isn't an EFI car. Can't expect it to behave like one.

Back in the day, even when everything was working right, at times we had to two foot it. Not bad with an automatic, two footing sucks with a manual.

Golly I like Carburetors, but with EFI, What can I say. Something about being able to go out and turn the key on a Zero day, have the engine compression stroke 4 times, pop to life and take care of itself. Freaking EFI has me spoiled.

Second place to look would be the high idle cam in the auto choke system. Make sure it's dropping and adjusted.
While the engine is completely cold, take the top off the air cleaner and look at the choke plates on the carb. They should be partially open.

Now step on the gas pedal to set the choke (about 1/4 pedal press if I remember).

Look at the choke plates again. They should now be completely closed (except for about 1/16 inch gap).

If they are not almost closed, then you need to turn the choke housing in the "Rich" direction. Check your Chilton's or Haynes manual for details.

After you start the car, the choke plates should remain almost closed for a few minutes and your engine should idle fast (about 1500 rpm). When you think the engine is warm (depends on your outside temp), tap the gas pedal to open the choke.

It should open at least half way, and your engine should still have a fast idle (about 1100 rpm). As it gets hot, the choke should open the rest of the way and the idle should drop to normal.

If the choke plates don't eventually open all the way and your idle drop to normal, then you need to adjust the choke housing towards "Lean".

It's at this point that I usually had some rough running and had to keep my foot on the pedal for another minute or so but usually only if it was pretty cold outside (around freezing). However I remember a drive once where the outside temp was in the low teens and the car would not warm up and the choke stayed on the whole way home! Of course it may have been due to my replacing the factory air cleaner with an open element chrome filter and not using the hot air tube from the exhaust manifold. ;)

Driving a car without EFI in winter requires that you keep the ignition tuned up and the carb and choke adjusted. Especially on a 2.3L or 2.8L engine.
Right. That makes sense as I remember doing this for my other car, which had an automatic (electric) choke. However, the II has a manual choke, which is a piece of junk haha.

Wouldn't it be a good idea to convert to a automatic choke?


- Brandon