I really need some help on what to check next.
So first thing in the morning cold start I go to start it and it acts like its flooded big time. starts but runs really rough and smells of fuel bad, white smoke out of exhaust. once it warms up it idles fine but still runs rich.
After the first start of the day it will be fine starting the rest of the day. It just runs rich. even if i let it set for 4 or more hours. But the next morning I go through the same thing.
Once its started and idling for about 4 minutes the check engine light comes on and throws a code 15. Coolant temp. I can turn it off and restart it and no light then 4 minutes later the light comes on again.
Here is what i have replaced some do to other issues.
Carb has been rebuilt and replaced including fuel filter inside carb, plugs, wires, distributor, cap rotor and coil. air filter, radiator hoses
I Have also replaced the coolant sensor on the intake manifold. replaced a lot of vacuum lines as they were old and cracked.
What next???? ecu?? any other sensors?
Thank you in advance
Thom

 

The best thing to do would be to put a scanner on it and see what coolant temp the ECM is seeing. It sounds like maybe you have an open or short circuit in the coolant temp sensor wiring (I can't remember which will make it see full cold) and the carburetor is fueling it for -30 degrees.

 

thats what im starting to think. It almost has to be electrical. Most of mechanical parts of the fuel system have been replaced besides the fuel pump.

 

If you pull the plug off the temp sensor and try it with the terminals shorted and then open, one way should make it run rich and one should make it run lean. If it makes no difference, there's probably something wrong with the wiring. You can also check to make sure you have reference voltage at one of the terminals on the connector.

Here's the relevant wiring diagram to show what's what.

 

thank you i will try that this weekend

 

Let us know how it goes.